The fantasy baseball ranking season is in full swing. For me, that typically starts with searching advanced stats leaderboards. Advanced statistics are often more predictive than traditional box score statistics. Thus, they’re an excellent jumping-off point. This series will dive into a variety of my favorite advanced metrics. However, I must caution that no statistic in isolation is the secret sauce for unearthing a hidden gem or burgeoning stud. Instead, they are a piece of the puzzle and best viewed through that lens, using other statistics in conjunction with them to formulate a well-rounded opinion of the fantasy value of players.
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Outside-Zone-Swing Percentage (Chase Rate)
Outside-Zone swing percentage (O-Swing%) measures the swings at pitches outside the strike zone divided by pitches thrown outside the zone. Thus, it’s good for a pitcher to have a high O-Swing%. Conversely, it’s good for a hitter to have a low O-Swing%. A low O-Swing% means hitters are spitting on pitches that aren’t strikes.
Now, let’s add some context. According to FanGraphs, a 31.3 O-Swing% was the league average for hitters in 2021. But, digging deeper, the lowest O-Swing% in 2021 among 132 qualified hitters was 15.1%, and the highest mark was a 48.3 O-Swing%.
Predictably, the leaders in chase rate were largely excellent at earning walks. The league average walk rate in 2021 was 8.4%. Interestingly, an 8.4 BB% was the lowest mark for the top-20 qualified hitters in O-Swing%. Moreover, 17 hitters had a 10.2 BB% or better in 2021 among the leaders in O-Swing%. Walks aren’t a category in traditional fantasy baseball formats. However, they help boost on-base percentage (OBP). So, they enhance the potential for scoring runs, which is a traditional fantasy scoring category.
The fantasy baseball ranking season is in full swing. For me, that typically starts with searching advanced stats leaderboards. Advanced statistics are often more predictive than traditional box score statistics. Thus, they’re an excellent jumping-off point. This series will dive into a variety of my favorite advanced metrics. However, I must caution that no statistic in isolation is the secret sauce for unearthing a hidden gem or burgeoning stud. Instead, they are a piece of the puzzle and best viewed through that lens, using other statistics in conjunction with them to formulate a well-rounded opinion of the fantasy value of players.
Dominate with our award-winning fantasy baseball draft software
Outside-Zone-Swing Percentage (Chase Rate)
Outside-Zone swing percentage (O-Swing%) measures the swings at pitches outside the strike zone divided by pitches thrown outside the zone. Thus, it’s good for a pitcher to have a high O-Swing%. Conversely, it’s good for a hitter to have a low O-Swing%. A low O-Swing% means hitters are spitting on pitches that aren’t strikes.
Now, let’s add some context. According to FanGraphs, a 31.3 O-Swing% was the league average for hitters in 2021. But, digging deeper, the lowest O-Swing% in 2021 among 132 qualified hitters was 15.1%, and the highest mark was a 48.3 O-Swing%.
Predictably, the leaders in chase rate were largely excellent at earning walks. The league average walk rate in 2021 was 8.4%. Interestingly, an 8.4 BB% was the lowest mark for the top-20 qualified hitters in O-Swing%. Moreover, 17 hitters had a 10.2 BB% or better in 2021 among the leaders in O-Swing%. Walks aren’t a category in traditional fantasy baseball formats. However, they help boost on-base percentage (OBP). So, they enhance the potential for scoring runs, which is a traditional fantasy scoring category.
In addition, many of the players in the following table are more valuable in leagues that use on-base percentage. Expanding on that, a .317 OBP was the league average in 2021, and every qualified hitter on the O-Swing% leaderboard had an above-average OBP, with 19 hitters sporting a .327 OBP or higher and 18 with an OBP north of .334.
2021 Qualified Hitters O-Swing% Leaders
Juan Soto (OF - WSH) is the class of exercising patience. He blew his peers out of the water regarding laying off pitches outside the strike zone. Shockingly -- I say sarcastically -- he led qualified hitters in walk rate (22.2 BB%) and OBP (.465).
Jonathan India (2B - CIN) and Joey Votto (1B - CIN) were also in the top-10 in OBP at eighth and ninth, with marks of .376 and .375, respectively. Max Muncy (1B/2B - LAD) and Mookie Betts (RF,CF,2B - LAD) are the only other hitters in the table that had a top-25 OBP last year. So, avoiding chasing pitches doesn't make a player a shoo-in to be among the OBP leaders. Regardless, it's a good recipe for getting on-base at an above-average rate, as I stated above.
Also, the table features vastly different skill types. For instance, Joey Gallo (OF - NYY is a three-true-outcomes posterchild, homering, walking, or striking out in 58.8% of his plate appearances in 2021. However, Myles Straw (CF - CLE) had just four homers and struck out in a modest 19.0% of his plate appearances last year. Instead, he's a speedster, making pitchers throw strikes and putting the ball in play to use his speed to put pressure on the defense.
Noteworthy Non-Qualified Hitters in 2021
Yasmani Grandal (C - CWS) was an offensive force last year. Sure, his .240 batting average in 375 plate appearances left something to be desired. Still, he used his patient approach to record a gaudy 23.2 BB% and eye-popping .420 OBP. The switch-hitting catcher also slugged 23 homers. So, obviously, Grandal is considerably more valuable in leagues that use OBP.
Unfortunately, Alex Bregman (3B - HOU) was on the Injured List for two months last summer. However, he exhibited his typical patient, high-walk, high-contact approach when he was on the diamond. Bregman's approach is outstanding. Still, I'm lukewarm on his fantasy outlook. Bregman has had only 18 homers and one stolen base in 580 plate appearances since 2020.
Finally, Evan Longoria (3B - SF) reinvented himself last year. It's unusual for a player in their mid-30s to have a resurgence like Longo did. However, the underlying metrics were excellent, easing concerns about his 2021 output being a fluke. Longo had a career-high 12.0 BB% and career-low 22.5 O-Swing%. The veteran third baseman paired his plate discipline excellence with outstanding batted-ball data. So, Longo is one of my favorite picks after 350, sporting an average draft position (ADP) of 383.7.
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Josh Shepardson is a featured writer at FantasyPros. For more from Josh, check out his archive and follow him @BChad50.
