Dynasty Fantasy Baseball Players to Sell (2021)

The fantasy football season is over and the actual football season is winding down, so it’s officially time (if you haven’t started already), to start focusing on fantasy baseball. For fantasy baseball managers in dynasty leagues, the season never really stops. These leagues typically have large rosters with room for prospects, and a successful team is often years in the making. 

The offseason is when savvy managers in dynasty leagues take a look at their roster and identify where they need to improve both in the short term and over the long haul. More importantly, though, these managers identify which players on their roster they should consider selling

In dynasty leagues, trades are a bit more complicated than in your typical redraft leagues. The wrong deal can be something you regret for years, as opposed to months. But the right deals can set you up for sustained success. The trick is often not just knowing which players to sell, but the right time to sell them. 

There are different reasons to sell players. You could be selling high after a breakout performance that you don’t expect replicated. You might sell a popular prospect at the height of his value, which is usually right before he is promoted. Or it’s possible you’ve spotted some red flags in a player’s expected numbers and are anticipating some negative regression. The list goes on, but the main point is that dynasty league trades have a multiple-year impact that needs to be considered.

With all of that in mind, let’s take a look at dynasty players you should sell ahead of the 2021 fantasy baseball season.

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DJ LeMahieu (1B,2B,3B – FA)

Having LeMahieu on the dynasty sell list may sound like blasphemy after he batted .364 and was a legitimate MVP candidate in 2020. But that’s exactly why he is a sell candidate. LeMahieu was always a good player with the Rockies, but he became a great player with the Yankees. He always hit for a good average but rarely offered much in the way of power. 

In 2019, with the help of juiced baseballs and Yankee Stadium, he hit .327 with 26 home runs, a career-best 40.4 Hard Hit%, an excellent HR/FB% of 19.3, and a .349 BABIP in 145 games. He was also 30 years old and had never hit more than 15 home runs in a season before. But his Statcast numbers backed up the performance. Other than the outside factors mentioned above, it looked legit. 

In 2020, though, it was more of the same. In an abbreviated season, LeMahieu put up similar numbers. His average jumped to .364, but his HR/FB and BABIP numbers were in the unsustainable category at 27.0% and .370, respectively. His xBA, xwOBA, xSLG, and Barrel% also indicate an above-average amount of good luck. In fact, LeMahieu’s wOBA-xwOBA (.067) and SLG-xSLG (.128) both led all of baseball (that’s bad).

Some players make their own luck, especially players who have excellent contact skills like LeMahieu. But we’re also talking about a player who is going to turn 33 years old during the 2021 season. Even if he experiences only some of the expected negative regression in 2021, is that player worth more than what he might fetch in a trade?

Brad Keller (SP – KC)

Keller is still just 25 years old and is coming off of an excellent (albeit abbreviated) season in 2020. So, why sell him? For starters, his value may never be higher than it is right now. 

Another reason is that there are signs that his 2020 breakout may not have been entirely legitimate. At least, there are some indicators that he could be due for some negative regression in 2021. If you look past Keller’s final numbers in 2020 to what his numbers could or should have been, you’ll see a different story.

Deep breath. Keller’s expected batting average, expected slugging percentage, expected xwOBA, expected ERA, FIP, xFIP, BABIP, and HR/FB% all indicate that he was lucky last season. On top of those numbers, he only struck out 5.76 batters per nine innings. And while striking out batters at above-average levels isn’t necessarily required for consistent success, pitchers who rely more on contact are more prone to bad luck over time.

Kwang Hyun Kim (SP – STL)

Kim came over from the KBO to the St. Louis Cardinals in 2020 and had an excellent season, pitching to 1.62 ERA and 1.03 WHIP while going 3-0 with a save over 39 innings. He made seven starts and allowed one or fewer runs in six of them. Everything is great. Right?

Well, not exactly. Kim only struck out 24 batters over 39 innings, and his 1.62 ERA comes with a 3.88 FIP and 4.52 xFIP. And while he kept the ball on the ground with a 50% ground ball rate, opposing batters also hit .197 against him in part because of a .217 BABIP. 

Kim came from the KBO to the MLB during one of the strangest seasons in history. It’s possible that, while he was an excellent pitcher in the KBO over the last few years, the odd circumstances of the 2020 season contributed to his success. 

Kim may very well remain a solid middle-of-the-rotation in 2021, but he’s unlikely to replicate his breakout rookie (he’s 32 years old, by the way) season. It’s time to sell high. 

Mike Yastrzemski (LF,RF – SFG)

Yastrzemski is a great story. He’s the grandson of the hall of fame Carl Yastrzemski who spent several years in the minor leagues before finally breaking through with the San Francisco Giants in 2019. Everyone can get behind that. It’s fun. It’s the American dream.

But he isn’t someone I’m tying myself to in a dynasty league. He strikes out roughly a quarter of the time, and I don’t trust that his high BABIP is going to continue. He hit 21 home runs in 107 games for the Giants in 2019 (and had 12 more in 40 Triple-A games) but had never hit more than 15 in a season in the minor leagues.

He was on a 30-home run pace in the abbreviated 2020 season, but most projections have him hitting somewhere around 20-25 and batting around .250. That’s a solid player, but if you can sell him based on his 2019 or 2020 production you might be able to get more for him in a trade that what he is going to be worth in a dynasty format.

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Mike Maher is an editor and featured writer at FantasyPros and BettingPros. For more from Mike, check out his archive, follow him on Twitter @MikeMaher, and visit his Philadelphia Eagles blog.