I dreamed up and created fScores during the 2021 baseball season and first introduced them at the start of the 2022 season. If you have been reading (@fantasyaceball on X) or listening to my content (the Fantasy Aceball Podcast), you have likely heard me reference fScores or use them to compare players. I realized there was one common issue with fantasy baseball player rankings — they don’t translate well to custom league settings.
Most sets of player rankings are built toward a traditional roto 5×5 setting and most people play in H2H categories or points leagues with custom settings.
How do we overcome this problem? I had the idea to create rankings based on core fantasy skills (named fScores for “fantasy scores”) rather than simply rank one guy over another guy based on standard fantasy baseball league settings. This way, if you play in a points league or an on-base percentage (OBP) league, something like plate discipline can be sorted to re-rank and re-weigh players for your specific league settings. Each fScore is weighted in the same measure as OPS+ or wRC+, where 100 is the league average. For example, 104 is 4% better than the league average.
- Fantasy Baseball Dynasty Rankings (2024)
- Fantasy Baseball Research & Advice
- Fantasy Baseball Average Draft Position (ADP)
- Fantasy Baseball News
fScore Hitting Factors
Six main skills go into an effective fantasy baseball hitter:
- fContact
- fPlate Discipline
- fPower
- fSpeed
- fDurability
- fEF (external factors)
Let’s go through these skills one by one where I’ll briefly describe what goes into each of these in my equation and also how each one plays off the other. In the following articles, I’ll go into the rankings and fScores position by position.
fContact
A hitter’s ability to make quality contact with the baseball weighed against an average MLB starter is fContact. Contact isn’t a direct correlation to batting average because the ability to reach base is also dependent upon power and speed. Is the hitter hitting the ball in the infield or the outfield? Is the contact a weak grounder or a line drive? Can the hitter outrun the throw from the fielder on a weak grounder?
Last year, I added some measures into the fContact algorithm (sweet spot % and Z-Contact %) to increase the measure of quality contact vs. bad contact. I added Z-Swing% into the algorithm this year, noting that aggressiveness in the zone directly relates to more quality contact and thus a higher batting average. Being overly passive in the zone can relate to lesser-than-expected results in creating damage (ie: Edouard Julien).
The way to think about contact in regards to fantasy stats is probably something like this:
- fContact + fSpeed = Batting Average above replacement player
- fContact + fPower = Home Runs above replacement player
With fContact, it’s built to eliminate luck from the equation by reducing the importance of batting average on balls in play (BABIP), but we should note some hitters naturally run a higher BABIP than others. This natural average BABIP per player is taken into account as we average out career BABIP against league-wide BABIP to create a base-line for each player.
How are fScores Weighed?
We weigh all of these fScores on the career totals along within the last three seasons (including additional weight on the last half-season).
- Career totals are given a 10% weight
- Three seasons prior is given a 10% weight
- Two seasons prior is given a 20% weight
- Last season is given a 30% weight
- The last half-season is given a 30% weight
How do fScores Project Forward?
Additionally, the total fScore is weighted based on expected 2025 fScore with a spread included on the way the player is currently trending. If a player is aging or injured and their skills are trending down, this will be seen in their future fScore. If the player is young and improving their skills, they will be trending up in their future fScore.
The aging curves below play a factor in future fScore as I have done a lot of research on the correlation of age to production and created an aging curve equation that plays into fScores.
Hitting Aging Curve (Based on wRC+)
What does this tell us?
- When 20- or 21-year-old players are promoted to the Majors they are likely to be superstars
- Peak years are between ages 26-32
- The first major drop-off is at age 33
- The second major drop-off off is at age 35
Pitching Aging Curve (Based on SIERA)
What does this tell us?
- When 20- to 22-year-old players are promoted to the Majors they are likely to be superstars
- There is a constant progression from ages 25-30
- The first drop-off is at age 31
- The biggest drop-off is at age 35
- Pitchers 38 or older are a different breed
Rookies/Small Sample Sizes
I spent a lot of time this offseason better perfecting rookie and minor league level-to-level correlations, including international correlations for players making the jump from Japan or Korea.
I took all qualified minor league hitters and pitchers (based on the below sample sizes from each of the two levels we are correlating against) to create an average correlation between statistics when making the jump from one level to another.
This is used to guide my rookie or even sophomore projections for 2025 fScores, including the elimination of reduction of the effect of certain measures that don’t translate well from minors to majors like HR/9 for pitchers.
Level-to-Level Correlations (2023 and 2024 data)
Hitters: 120 at-bats minimum for players who played at each level when going level-to-level.
- K% stabilizes at 50-60 plate appearances
- BB% at 120 plate appearances
- Contact% at 100 plate appearances
- GB/FB rate at 80 BIP
- ISO at 160 at-bats
- Slugging (half-season), OBP (three-quarters of a season), batting average & BABIP (one-and-a-half seasons)
Starting Pitchers: 40 innings pitched minimum qualification.
- K% stabilizes at around 15-20 innings pitched
- BB% at 40 innings pitched
Confirmations
- AAA is terrible for pitchers and the data is so volatile that AA stats are a better measure of performance once they get to the majors
- Jump to the majors is extremely difficult (especially for hitters with bad plate skills)
- NOTE: Walk rate improves for pitchers from AAA to MLB
- Strikeouts go way down as hitters have a much better contact rate in the majors
- NOTE: Walk rate improves for pitchers from AAA to MLB
- A+ to AA is easy
- CPX to A is hard
Betas
I created a simple Beta metric to provide a volatility guide year-over-year for hitters and pitchers to help us get a measure of risk between different players. It should be noted this Beta is based on only three data points (each of the three years measured in the formula — 2022, 2023 and 2024, to be more specific). If a player is missing a data point, they do not have a Beta.
I would have had a more accurate measurement had I used more data points, like monthly or weekly data points, but it would have been more work than I was willing to do for this measurement. Feel free to take this and run with it if you’d like.
Findings guide that an under five Beta in this model more or less results in a consistent player and the greater than five players are much more volatile in production year over year.
- Based on a minimum of three years of data of at least 160 plate appearances or 40 innings pitched*
- Relief pitchers are not factored into the Beta equation on the pitching end
- Hitting Beta based on wRC+
- Pitching Beta based on SIERA
*Note: Injured players from last year won’t have a Beta.
What Stats Go Into fContact?
A weighted aggregate consisting of stats such as BABIP, batting average, Zone Swing %, Zone Contact %, reverse IFFB% (pop-ups are wasted outs) and Sweet Spot % is fContact.
fDiscipline
The hitter’s ability to judge the strike zone, see breaking pitches, take walks and avoid strikeouts against an average MLB started is fDiscipline.
This isn’t a direct correlation to OBP because it’s also taking into consideration avoiding strikeouts and hunting good pitches to hit, so technically a higher fDiscipline will likely also lead to a higher batting average, higher home run total, higher run total and a higher stolen bases total. This fDiscipline component complements all other skills and boosts the ability to achieve higher stat totals all around. It’s also very important for younger hitters when projecting their future growth as a hitter.
What Stats Go Into fDiscipline?
Aa weighted aggregate consisting of stats such as BB%, K%, chase rate (O-swing%) and SwStr% is fDiscipline.
fPower
A hitter’s ability to consistently hit the ball out of the park or hit line drives that lead to extra-base hits against an average MLB starter is fPower.
This is not a direct correlation to OPS or home runs because fContact and fDiscipline must be achieved to hit the ball enough times to make fPower meaningful while fSpeed will increase the ability of the hitter to turn hard-hit balls in the outfield into extra-base hits.
What Stats Go Into fPower?
A weighted aggregate consisting of stats such as ISO, barrel%, HR/FB, reverse GB%, average EV and even home ballpark home run splits in the event of a park change based upon handedness make up fPower.
fSpeed
A hitter’s pure speed matched with the ability to steal bases is fSpeed.
This is not a direct correlation to SB, because the hitter has to be able to get on base to steal bases. Also, fSpeed’s weighed footspeed is heavier than stolen bases – caught stealing because fSpeed is an important skill to correlate to base hits and extra-base hits when paired with fContact and fPower.
What Stats Go Into fSpeed?
A weighted aggregate consisting of stats such as stolen bases – caught stealing, hits and walks and 90-foot speed splits based on handedness make up fSpeed.
fDurability
A hitter’s ability to stay healthy, play games and be good enough to garner consistent at-bats against an average MLB starter is fDurability.
This should be used primarily as a way to measure a player’s skill with their ability to stay on the field and produce. If a player scores above average in all of the other skills, but can’t stay healthy (ie: Byron Buxton or Adalberto Mondesi), then it’s going to impact their total value to your fantasy team.
What Stats Go Into fDurability?
A simple weighted aggregate of games played and at-bats against the average MLB starter make up fDurability.
fEF (External Factors)
External factors weigh important factors that are not necessarily individual skills into the fScore equation to help provide a better ranking and read into how each player will accumulate counting stats.
What Stats Go Into fEF?
External factors include home park ballpark factor splits for handedness, projected lineup spot based on a custom correlation of lineup position to counting stats, average counting stats and wRC+ of the surrounding lineup.
fScore (Total and Future)
The provided total fScore is based upon a weighted average of fContact, fDiscipline, fPower, fSpeed and fDurability because all five skills play off each other. External factors get multiplied directly into the overall fScore.
In my latest fScores, I weigh contact, power and durability as more important metrics than discipline and speed.
Future fScore considers the trending nature of all the stats aggregated into the fScore skills. They take into account the following questions:
- Are the consolidated skills on average trending up or down?
- By what percentage are they trending up or down?
- What is the age of the player in question?
- Where are they on the aging curve?
When you take fScore and future fScore it should provide you with a range the player should fall between, not taking into consideration any major player skill or habit changes such as swing change, diet change or workout regimen change that happens outside of the standard deviation of volatility in the sport.
Using fScores, a fantasy baseball player can change how they weigh the skills or grade players based on a skill that can provide an advantage to them in the settings of their fantasy baseball league.
fScore Pitching Factors
Four main skills go into an effective fantasy baseball pitcher:
- Durability (fPDurability)
- Stuff (fStuff)
- Control (fControl)
- Run Prevention (fERA)
NOTE: Run Prevention is designated by fERA and has within it a subcategory weighing pitching external factors (fPEF), such as defense behind the pitcher and home ballpark.
Let’s go through these skills one by one where I’ll briefly describe what goes into each of these in my equation and also how each one plays off the other. After we go through the skills, I’ll go into the rankings and fScores for starting pitchers and relief pitchers.
fPDurability
A pitcher’s ability to stay healthy and pitch deep into games against an average MLB starting pitcher or relief pitcher is fPDurability.
This should be used primarily as a way to measure a player’s skill with their ability to stay on the field and produce. If a player scores above average in all of the other skills, but can’t stay healthy (ie: James Paxton or Chris Sale), then it’s going to impact their total value to your fantasy team.
The way to think about fPDurability in regards to fantasy stats is probably something like this:
- fPDurability = Innings pitched above replacement player
- fPDurability + fStuff = Strikeout totals above replacement player
- fPDurability + fERA = Better overall assistance in ERA, quality starts or wins above replacement player
Higher fPDurability pitchers will positively or negatively impact ratio stats for pitchers when weighed against the totals of your other pitchers.
How are fScores Weighed Season by Season?
We weigh all these fScores for pitchers on the player’s last three seasons (including additional weight on the last half-season).
- Three seasons back is given a 15% weight
- Two seasons back is given a 25% weight
- Last season is given a 30% weight
- The last half-season is given a 30% weight
Pitching fScores have both a standard fScore and a future fScore just like the hitting fScores. The standard fScore is what the skills point to that player achieving whereas the future fScore is based on trending what the player’s likely ceiling on the season is from their expected outcome based on previous skills shown.
This can also lead to wider margins from players coming off of significant injuries as the range of durability might expand for example if a player had Tommy John surgery in 2023 (thus did not pitch in 2024 and will bring the fPDurability score down), but is expected to pitch a full year in 2024 and might reach 120-160 innings.
What Stats Go Into fPDurability?
A fPDurability score is determined by taking average season innings pitched totals, games started totals and innings pitched/games started totals for starters and weighed against the league average starter. Relief pitcher fPDurability totals are weighed against league-average relievers, rather than starters.
One thing to keep in mind with pitchers is they are about 20% more prone to serious injury or Tommy Joh surgery than position players. This is a topic I spent a lot of time researching this season.
As a result, I have created an additional durability factor based on ligament age for pitchers using the following chart:
Rookies/Small Sample Sizes
As with hitting fScores (and even more so with pitching) I don’t have as much information to pull from at the Major League level and have had to attempt to synthesize their Minor League stats at approximate averages based on the above-noted level-to-level correlations.
This by no means is a perfect translation from Minor League stats to Major League stats. Many of the fScores utilize Statcast data, which is more or less not provided for minor leaguers. This should be kept into consideration when analyzing the fScores of minor leaguers and prospects, rookies and anyone with fewer than two seasons of experience at the Major League level. From my findings, fStuff and fControl are more predictive for rookies than externals or fERA.
fStuff
A pitcher’s ability to throw effective strikes that lead to strikeouts or progressing in the count is fStuff. We all love pitcher stuff, right? Well, fStuff is what leads to the fun Pitching Ninja gifs we pitching nerds watch all day.
This isn’t a direct correlation to strikeouts because we don’t have any way to measure pitch sequencing effectiveness, but it measures the important traits of getting non-foul ball strikes.
What Stats Go Into fStuff?
A weighted aggregate consisting of stats such as CSW%, K%, swinging strike rate, fastball velocity along with Eno Sarris’ Stuff+ and Stuff+ FA is make up fStuff.
fControl
A pitcher’s ability to avoid walks and pitch in or around the strike zone effectively against an average MLB starter is fControl.
This is a close correlation to WHIP and to avoid walks in general.
What Stats Go Into fControl?
A weighted aggregate consisting of stats such as WHIP, BB%, first pitch strikes (f-str%), pitcher (chase rate) O-swing% and Eno’s Location+ make up fControl.
fERA
A pitcher’s ability to limit runs against is fERA.
What Stats Go Into fERA?
A is a weighted aggregate consisting of stats such as SIERA, ERA, BAA, HR/9, Barrel%, home ballpark and defensive factors make up fERA.
Also impacting fERA are pEFs (pitching external factors). What goes into this calculation are park factors for the pitcher’s home park and team defense behind the pitcher with a custom correlation taken by averaging team (defensive runs saved) DRS, team outs above average (OAA), team defensive efficiency factor (DeF) and arsenal effects.
Some studies show pitchers with three or more pitches are more likely to go deep and snag quality starts, so the quantity of plus-pitches is factored into pEFs.
fScore (Total and Future)
The provided total fScore is based upon a weighted average of fPDurability, fStuff, fControl and fERA because all four skills play off each other.
Two — fStuff and fPDurability — are weighted a bit higher than fControl and fERA, as I believe fStuff correlates better year over year and is more sticky than the other fScores.
Future fScore considers the trending nature of all the stats aggregated into the fScore skills. They take into account the following questions:
- Are the consolidated skills on average trending up or down?
- By what percentage are they trending up or down?
There is an additional factor added into fScores for the width of the arsenal. Having three or more pitches correlates with an increased ability to regularly go six or more innings, which will increase the odds of getting wins or quality starts.
When you take fScore and future fScore it should provide you a range that the player should fall between, not taking any major player skill or habit changes such as developing new pitches, velocity uptick from previous seasons, diet change or workout regimen change that happens outside of the standard deviation of volatility in the sport.
Using the spreadsheets from future articles, a fantasy baseball player can change how they weigh the skills or grade players based on a skill that can provide an advantage to them in the settings of their fantasy baseball league.
Future articles will go position by position using my fScores spreadsheets and discuss player rankings and tiers. By providing each player a fScore, tiering players out is more clear than ever before.
Additionally, you will note I do not follow my rankings by the fScores to a tee but rather use them as a strong guideline. I may shift players up or down based on my biased notions of perceived progress or the possibility of avoiding injuries or getting better in certain areas that can’t be shown by numbers scouting, which the fScores undoubtedly are doing.
Now you know what fScores are and why they are such a great tool for you to use in all your fantasy baseball pre-draft prep.
Subscribe: YouTube | Spotify | Apple Podcasts | iHeart | Castbox | Amazon Music | Podcast Addict | SoundCloud | TuneIn
Please follow me on X @fantasyaceball, on YouTube @TheTimkanak and subscribe to the Fantasy Aceball podcast for more great content throughout the season. More of my written work can be found here on FantasyPros.