Managing Prospect Expectations

© Staff Photo by Richard Pollitt via Imagn Content Services, LLC

Every offseason, we work diligently to produce prospect rankings for every team in baseball — when all is said and done, our lists typically incorporate well over 1,000 player write-ups. And based on the engagement with last week’s Top 100 Prospects list and our other Prospects Week content, our readers are as excited about prospects as we are. I’m proud of the work we do here at FanGraphs, but there is one area in which we haven’t done as well as we could, and that’s in helping you properly manage expectations.

We see it in the comments, on Twitter, and in pieces at other publications that reference the work done here. People line up a team’s prospect list and assume that is what the team will look like in two, three, or more years. Look up a system’s top five pitching prospects and that’s what the big league rotation will look like down the road. Three good middle infield prospects? That’s too many! What will the club ever do? We’ve tried our best to communicate the exceptionally real (and yet still underrated) failure rate when it comes to projecting prospects, but it’s become clear that we haven’t done a good enough job.

On our Top 100, we included Estimated Probable FV Outcome distribution graphs with each writeup in an attempt to better communicate the chances of each player becoming a big leaguer, let alone a good or even great one. As an example, here is Nick Pratto’s distribution graph:

Those numbers weren’t set out of the blue; we based them on historical data on how prospects given 50-grade or higher FVs actually turn out in the end, and then applied our own judgements about the player.

People spend a lot of time looking at the right side of the scale and with good reason. That’s where the fun is. That’s where stardom lies, where team wins comes from. But too often, we ignore the left side, the role player side, the (gulp) bust side, where the data shows an overwhelming chance that none of this will work out the way some fans might hope.

I think our Top 100 is really good, but I also buy the research that suggests that a meaningful percentage of these players just aren’t going provide any major league value. None. Zero. Zilch. Nada. Indeed, if we average the bust odds for all 114 ranked prospects and apply that average to the population, we can get a rough idea of how many of the those players we might expect to bust — in this case, about 36 players.

Properly setting readers’ expectations is perhaps best done by starting with an extreme example. Right now the Baltimore Orioles have the best position player prospect in baseball, as well as the best pitching prospect in the game. Indeed, Adley Rutschman and Grayson Rodriguez are one of the better hitter/pitcher combos in a single organization in recent memory, and their expected outcomes are equally impressive:

The Orioles Big Two: Expected Outcomes
Bust 40-45 50-55 60-65 70
Adley Rutschman 12% 18% 20% 20% 30%
Grayson Rodriguez 15% 15% 25% 25% 20%

But let’s do the math. As the top prospect in the game, we are saying, and I think accurately so, that Rutschman is the most likely perennial MVP candidate on our list. We’re saying the same for Rodriguez in term of his year-to-year Cy Young chances. Their odds of becoming a 70+ FV player aren’t topped by any other prospect in their player group. But the chances that both end up being that player? How about just 6%, or roughly 1-in-16, because that’s what the math tells us. Let’s lower expectations, and see what the chances are that both become star-level players (60+ FV). That’s 22.5%. Think about that for a second. This is, once again, the best position player prospect and the best pitching prospect in all of baseball. The chances of both becoming stars is outstanding compared to any other combination you might come up with, but it’s also less than 1-in-4. Assuming Rodriguez will be the staff ace and that Rutschman will be a perennial All-Star? The odds are stacked against that, and in fact, quite strongly. That said, the chances are good that they’ll provide something. There’s a 91% chance that both will be big leaguers, using the low bar of both becoming a 40+ FV. But the odds that only one of the pair provides big league regular level performance (50+ FV) are exactly the same as both doing so:

Being Realistic About Outcomes
Outcomes Odds
Both will be 50+ FV 45.5%
One will be 50+ FV 45.5%
Both are busts 9%

Both of them working out, even just in terms of being big league regulars? Probably not. Just barely probably not, but nonetheless under 50%. And this is in no way an indictment of the players or their respective rankings; it’s an indictment of how prospect rankings are perceived following their release.

We can do this math with any pair of highly regarded prospects. The Tigers have first baseman Spencer Torkelson and outfielder Riley Greene sitting as the fifth and sixth best prospects in baseball. The chances both of them are 60+ FV stars? That comes out to 17.1%, or roughly 1-in-6. The chances that both are 50+ FV big league regulars? Just over 40%. Again, the most realistic outcomes are those other than both players becoming even major league average regulars or better.

This is why teams need depth as much as star power. The more high-end prospects a team has, the better those outcomes become, not in terms of them all working out (that’s never going to happen), but in terms of some working out.

Still, there is incredible risk, especially when a system is populated by players who are still very far away. A great example is the Chicago Cubs, a team that has an incredible number of intriguing, high-upside prospects, many of whom are still teenagers. Four such players are in the bottom part of our Top 100, ranking from No. 87 to No. 114. But Cubs fans who are already pencilling Kevin Alcantara, Owen Caissie, James Triantos and Reginald Preciado into their favorite team’s 2025 lineup are setting themselves up for considerable disappointment:

Attrition Can Be Brutal
Outcomes % Chance
All Four 50+ FV 1.0%
3-of-4 50+ FV 8.9%
2-of-4 50+ FV 28.4%
1-of-4 50+ FV 40.3%
Zero 50+ FV 21.4%

And to be clear, these are not their chances of stardom; these are just the odds of them being major league regulars at an average or better clip. They’re a wonderful quartet of players, but the realistic odds are set at just over 90% that half or more won’t live up to what amount to only moderately lofty expectations.

Prospects are great, prospects are fun, and prospects are exciting. They can offer an enticing glimpse of how your team gets better. But that doesn’t mean they will. No team in baseball can build a champion entirely from within. Even the team with the best system is baseball — and even a system that enjoys better-than-expected outcomes from its bulk of prospects — at some point needs to spend money and/or trade said prospects in order to improve its roster from the outside. As my good friend Jason Parks used to say, “Prospects will break your heart.” It’s always important to have that in the back of your mind when accurately considering the future of an organization.

Kevin Goldstein is a National Writer at FanGraphs.

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8 months ago

Thanks for writing this! It is natural to be excited about prospects but every baseball fan should read this. As a Braves fan, the example I always think of is Jason Heyward. At one point he was the top prospect in baseball. When he came up and slugged his first big league home run Braves fans were dreaming on him batting in the middle of the order and hitting 30+ bombs a year for the next decade+. But that didn’t happen. Most would say Heyward was a disappointment. But here he is with 30+ career WAR. He’s been a solid to good player for 12 seasons. I don’t know what his FV was when he was a prospect and even if 30+ WAR is not the top percentile, that’s a really good career outcome.

Last edited 8 months ago by kylerkelton
8 months ago
Reply to  kylerkelton

Jason Heyward is by any rational standard an enormous success, but that seemed to me to be the golden days of overhyped prospectdom. He was getting Dave Winfield comps. No one should be getting comped to a Hall of Famer unless you’re talking about the 90th percentile outcome, and even then…

8 months ago
Reply to  sadtrombone

Overhyped prospectdom is correct. I remember hearing Hank Aaron comps.

8 months ago
Reply to  Francoeurstein

Comps always lead to disappointment, or most of the times. I usually argue against them, but occasionally I’m forced to admit I was wrong. When Aaron Judge arrived, I saw more than a few people compare him to Giancarlo Stanton, then of the Marlins. I said he might be good, but don’t put the Stanton comp on him expectation wise. Well, the comp actually wasn’t bad from a success factor, even if their styles a bit different. Judge is a better fielder and more patient. Then there was the Mike Trout comparisons to Mickey Mantle before Trout played a game in the majors. I laughed at that one, even though I was a big Trout fan, and yet Trout really has been Mickey Mantle. Still, these comps hitting are very rare, and mostly lead to fan disappointment.

The Strangermember
8 months ago
Reply to  sadtrombone

The perception of Jason Heyward is definitely colored by his meh performance as a Cub. He was really good with Atlanta and St. Louis., easily within that 60+ FV bucket that represents the top half of expected outcomes for any player. He just dropped off fast after that.

Incidentally, in looking at his player page to write this reply, I saw that his wOBA in his 2015 walk year was a fairly robust .346, which was very much in line with his career to that point. But unfortunately for the Cubs, his xwOBA was .296, which makes his performance since then less surprising.

That being the first year of Statcast data, though, I don’t know how many teams had figured out something along the lines of xwOBA at that point. Kevin, any insight?

8 months ago
Reply to  sadtrombone

the golden days of overhyped prospectdom” I don’t really think we’re out of that yet, given how often I see fans bringing up Buster Posey comps for Adley…

8 months ago
Reply to  zurzles

I will reiterate my prediction that Adley’s career will fall somewhere between that of Matt Wieters and that of Buster Posey. #boldpredictions2022

8 months ago
Reply to  zurzles

Some people are still comparing Bart to Posey, which is really ludicrous.

8 months ago
Reply to  zurzles

Also, remember Matt Wieters as “Mauer with Power”. Eeegads. There are still lots of people out there like that but I think (some) people writing up prospects in the media are less likely to advance it.

8 months ago
Reply to  kylerkelton

30+ WAR would be an incredible projection for any prospect, 95th percentile I would guess.

8 months ago