On Tuesday's episode of the Fantasy Baseball Today podcast, we talked about the impending call up of Blue Jays top prospect Alek Manoah and what we expect from him as a rookie -- quite a lot, hopefully! But then the conversation turned to a more broad question: Have rookies been abnormally disappointing lately?
There have been impact rookies who have made their debut this season, of course -- Yermin Mercedes, Adolis Garcia, and Jazz Chisholm have all been difference makers when in the lineup, to name three. But it's not like those three were exactly incredibly hyped coming into the season, while the likes of Andrew Vaughn, Logan Gilbert, Daniel Lynch, haven't made quite the immediate impact we hoped for. Anecdotally, it does seem like there haven't been quite as many top prospects to hit the ground running either this season or last season, and the numbers do bear it out: Rookies have been less productive lately.
In 2020, non-pitcher rookies collectively hit .232/.299/.369 with an 83 wRC+ -- a measure of overall hitting production that scales to 100 as league average -- the lowest mark since 2015 and the fourth-lowest for a season since 2000. In 2021, things have been even worse: Rookie hitters are hitting .214/.288/.354 with a 79 wRC+, the lowest since 2000.
It's still early enough that this could be a bit of a fluke, but rookies are striking out 20% more often than the league as a whole, the fourth time since 2000 where the difference has been at least that big. And, of course, because strikeouts are up to record highs already, that means things are even worse for rookies right now, as they sport a collective 28.2% strikeout rate, compared to 25.2% in 2018, the previous record high before 2020 -- rookies struck out 27.1% of the time last season, too:
Rookie K% | League K% | |
2000 | 17.90% | 15.90% |
2001 | 17.80% | 16.80% |
2002 | 20.00% | 16.30% |
2003 | 18.80% | 15.90% |
2004 | 19.80% | 16.30% |
2005 | 18.10% | 16.00% |
2006 | 18.30% | 16.30% |
2007 | 19.10% | 16.60% |
2008 | 20.60% | 17.00% |
2009 | 19.90% | 17.50% |
2010 | 20.40% | 18.00% |
2011 | 20.00% | 18.10% |
2012 | 20.50% | 19.20% |
2013 | 21.80% | 19.30% |
2014 | 22.90% | 19.90% |
2015 | 23.30% | 19.90% |
2016 | 23.00% | 20.60% |
2017 | 25.00% | 21.20% |
2018 | 25.20% | 21.70% |
2019 | 24.80% | 22.40% |
2020 | 27.10% | 23.40% |
2021 | 28.20% | 23.50% |
Relative to league average, this is also the worst performance by rookie hitters as a whole in each triple-slash line category since at least 2000.
What about pitchers?
The effect hasn't been quite as pronounced on the pitching side, but it's definitely there. Rookie starters are sporting a 4.71 ERA collectively compared to a 4.07 mark for the league as a whole; that is 15.7% worse, the largest gap since 2004 and the second largest since 2000 overall. Typically, rookies as a whole are around 10% worse than the league as a whole -- though last season, they were only 2.7% worse, which is interesting.
Strikeout and walk rates for rookie pitchers have held pretty steady among rookies, relative to the league this season, so the biggest issue is with homers; rookies are surrendering 1.57 HR/9, compared to just 1.22 for the league as a whole, a whopping 28.7% worse than league average. That is by far the worst mark since 2000, but it's hard to necessarily find a good reason for it. On the whole, however, the collective xFIP for rookies -- which attempts to normalize home run rates -- suggests they've been about the same as ever.
So it could be a fluke there, too. Or, it could be that rookie pitchers on the whole just haven't been quite as precise as they need to be, and it's manifesting itself in more meatball pitches. That could be a reflection of rust and lack of experience, though given that the changes aren't quite as steady across the board as they are for hitters, it seems more likely to be just a bit of noise here.
Why is this happening? What does it mean?
Well, it's hard to say what, exactly, is happening. Maybe the quality of rookies getting called up this season is just a little bit lower, collectively, than we're used to. Obviously, that would be tough to quantify, but only three of Scott White's top 13 prospects coming into the season have played in the majors so far. And, potential impact rookies like Alex Kiriloff, Nate Pearson, Sixto Sanchez, and Ke'Bryan Hayes have struggled with injuries, too.
Maybe teams have been forced to lean on rookies more often than normal, exposing players to more playing time than they are necessarily ready for? Given the glut of injuries of late, it seems like a reasonable explanation, though the numbers don't necessarily bear that out:
Percentage of each by rookies:
Season | GS | PA |
2000 | 14.45% | 10.23% |
2001 | 17.70% | 11.30% |
2002 | 18.73% | 9.61% |
2003 | 16.32% | 12.90% |
2004 | 9.29% | 11.83% |
2005 | 12.48% | 14.00% |
2006 | 19.60% | 13.05% |
2007 | 16.25% | 12.36% |
2008 | 16.97% | 13.10% |
2009 | 20.74% | 11.76% |
2010 | 11.63% | 13.40% |
2011 | 13.34% | 13.53% |
2012 | 18.48% | 12.51% |
2013 | 15.10% | 12.57% |
2014 | 15.12% | 13.09% |
2015 | 18.05% | 15.61% |
2016 | 16.56% | 12.23% |
2017 | 16.63% | 14.53% |
2018 | 17.46% | 14.16% |
2019 | 18.69% | 16.17% |
2020 | 20.38% | 12.24% |
2021 | 17.53% | 11.94% |
Rookie starting pitchers have been used about as often as we're used to seeing, while rookie hitters have actually taken up a lower percentage of total PA this season than any since 2004.
Maybe Jarred Kelenic gets hot, Vidal Brujan, Wander Franco, and Jo Adell get called up, and Sanchez, Hayes, and Kiriloff can come back healthy and that will turn the trend around, but it's worth considering the possibility that maybe this isn't just a fluke; maybe top prospects are simply more likely to struggle immediately upon getting called up right now?
It would make sense if that were the case, of course. There were no official minor-league games last season, and this year's minor-league season didn't get started until earlier this month. That means the rookies who were called up last year were doing so without having played a real game all season, the rookies who were called up in April of this season hadn't played in a real game since 2019, and those called up May have had just a few weeks worth of games since 2019.
These players haven't been idle, of course, but you can't replicate real games in a controlled environment like the one teams were conducting at their alternate sites last season and in April. You're facing the same groups of players in a relatively low-stress environment where winning isn't necessarily the goal. It'll take a few years to see what, if any, impact that had on long-term development -- you could argue it might have been good for it -- but in the short term, it wouldn't be surprising if it had a negative effect on the immediate readiness of players getting called up.
We've been a little underwhelmed by the early play of Andrew Vaughn, Casy Mize, and Logan Gilbert especially, three players who were praised for their readiness and maturity but who hadn't actually logged much time as a professional in the minors. We saw something similar last season with Jo Adell, who had just 224 career games as a pro before his disappointing call up.
Maybe it's not a coincidence? Maybe the extreme circumstances of the last year-plus have created an environment where it's just harder to produce as a rookie? Maybe the lack of real game competition has made it harder for teams to know which players are actually developing as expected?
Or maybe it's just a weird couple of months. It could be that, too. These trends don't necessarily make me any less enthusiastic about adding Alek Manoah, and I'm not going to drop Wander Franco where I've been stashing him. The top prospects still hold so much value not because they are guaranteed to be stars but because those that hit provide some of the best return on investment of any players in Fantasy.
But if you're waiting on Manoah or Franco (or Brujan or whoever) to save your season, just keep in mind there's no guarantee. And maybe it's worth exploring trades with those players more aggressively than usual, because their perceived value may never be higher than when they first get the call. Because this game isn't easy, and it might be harder for rookies than normal right now.