I have to give a hat tip to two commentators for writing my post for me, essentially. Vesuvius looked at AAA hitters with a 30% K rate in the past and was not terribly enthused with the list and then country stuff added in hitters with a fairly low BB rate with that 30% K rate and came to the same conclusion. So I’m essentially just giving this idea a broader platform.
If you regularly read the comments, you know who I’m talking about. For everyone else, this is commenting on Joshua Baez’s AAA performance
this year. Joshua Baez is currently running a 31 K% and 7 BB%. At this point, I’m not even put off by the K rate that much with his power. I am put off by his K rate combined with the walks though. That’s not a good combo and it typically gets worse when a player is promoted. But let’s back this up with examples.
First off, there have been 119 players with at least 250 PAs who have carried a 30% K rate or higher since 2006. That’s too many. Let’s put further restrictions on it. Let’s say hitters with a 30% K rate at age 24 or earlier, because obviously if a 26-year-old is running a 30% K rate, that’s not the same thing. That cuts the list down to just 28 players. I was kind of shocked by how few this was, but it makes sense if you think about it. If you’re 22 and you make it to AAA, typically you do not have huge strikeout problems. And if you do, typically it’s because you have big power. And this mostly holds true. Most of this group has pretty good pop, at least in AAA.
Out of this group of 28 players, 15 of them carried a walk rate 8% or lower. That’s our sample group here. Before I list the players, I want to make it clear: this is an argument that Baez needs more time in AAA, not an argument that he won’t succeed at the MLB level. I have season-level data on these players, but I’m sure there are other players who carried a 30% K rate for a 250 PA sample and 8% or lower BB rate, but then at some point, those numbers got better and they aren’t on this list. Just have to make that clear.
Our first example is confusing. I don’t know that I’ll go into this much detail on other players, but the oddness of this one has to be shared. Over the 2015-2016 offseason, the Padres traded Craig Kimbrel to the Boston Red Sox for four players, one of whom was the 52nd ranked SS prospect Javy Guerra. Guerra was about to be 20 and hitting High A. He didn’t hit in High A, so he repeated the level in 2017. He still didn’t hit but he ended the year in AA anyway. He didn’t hit in AA either. For some reason, the Padres put him in AAA at age 22. He struck out 35.8% of the time and walked 5.8% of the time. They moved him to pitcher. This is just bizarre roster management to me but okay. Very bad comp for Joshua Baez to say the least.
The other 22-year-old on this list has just as strange of a story and quite tragic. Greg Halman reached AA at age 20 in 2008. He was slightly above average. He was actually worse the next season, with an 87 wRC+ but was promoted to AAA anyway. I assume I’ll find a player who was promoted who was an actually good hitter in AA at some point. Halman struck out 36.3% of the time and walked 8% of the time and had a 115 wRC+ thanks to a .302 ISO. He was very bad in his 9 game sample at the MLB level that year.
He repeated AAA, lowered his K rate to 27%, but lost most of his power, but thanks to a .413 BABIP, he still had a 105 wRC+. He got a second crack at the MLB, getting 91 PAs in 35 games. He struck out 36% of the time, walked 2% of the time, and had a 68 wRC+. Unfortunately, his story ends here. Over the next offseason, he was stabbed by his brother in Rotterdam and died. His brother was acquitted due to temporary insanity with supervision from a probation officer and to undergo mental health treatment.
Okay now to the 23-year-olds, the directly comparable age that Joshua Baez is. Sheldon Neuse isn’t a great comp either to be honest. He basically jumped from A ball straight to AAA, playing a combined 40 games at High A and AA. His K/BB numbers came with a .094 ISO. When he repeated the level, he had a normal BB rate and normal K rate and a .233 ISO, but it was a crazy offensive environment because despite that and a .384 BABIP, he had just a 113 wRC+. His numbers didn’t translate to the majors whatsoever and his career ended with a .094 ISO. So clearly, he’s a bad comp because he just doesn’t have Baez’s power.
We have a pending example in Colby Thomas of the Athletics. He reached AAA fairly quickly, getting drafted out of college in 2022 and reaching AAA by 2024. Again, the AAA affiliate of the Athletics has a ridiculous offensive environment because he had a .383 wOBA and…. a 109 wRC+. Anyway, he played in 73 games, and spent most of 2025 in AAA, with vastly improved strikeout numbers. Nonetheless, in his 79 games at the big leagues so far, he has a 5.6 BB% and 34.2 K%.
Kyle Skipworth is living up to his name because he is worth skipping. He was a catcher and never at once a good hitter in the minor leagues. Michael Gettys isn’t that extreme, but he was a below average hitter above A ball, so we’re going to skip him too. And that’s the entire list of 23-year-olds. The two best comps we have so far haven’t been completed. Ones life was unfortunately ended early and the other is still playing, though the numbers aren’t great. That said, Colby Thomas was nowhere near Joshua Baez as a prospect, and it doesn’t really look like Fangraphs bought into his power numbers.
Jason Vosler is an interesting case. He didn’t actually strike out very much until he reached AAA at 24. His K/BB numbers improved drastically the next season, but he was still a barely above average hitter and as it turns out, he has struck out 29.2% of the time at the MLB level with a career 82 wRC+. Vosler was ranked 19th in the Cubs system for the 2018 season.
Chris Shaw narrowly missed the age 23 season with a K rate just under 30%, but he landed there his next season. His walked rate declined to 5% and his K rate rose to 34.1% and he still managed a 111 wRC+. As you can imagine though, this translated to a career 37.8 K% at the MLB level. His age 23 is close to a good comp, but he actually walked less and seemingly regressed as a hitter in his second stop at AAA. The season that landed him on this list is a very bad comp.
Edwin Rios is almost on this list twice. He actually reached AAA for a 190 PA sample at age 23, posted a 9.5 BB%, 22.1 K%, and a 125 wRC+. When played in AAA again, his BB rate collapsed to 6.7% and his K% rose to 32.3%. He repeated AAA and narrowly missed the walk cutoff, walking 8.3% of the time, but he struck out even more. He has gotten 335 career PAs in parts of six seasons and has a 100 wRC+ with a 33.7 K% thanks to a .253 ISO, but his strikeouts got kind of out of control in his last three seasons and he was sort of a man without a position, so this didn’t translate to much WAR.
Shay Whitcomb had a 70 wRC+ with his terrible K/BB numbers, repeated AAA and suddenly walked 11% of the time with a 19% K rate. But he’s barely gotten a shot in Houston and was recently sent down after striking out 45.8% of the time in 24 PAs in 17 games this season. He’s only got 102 career PAs in 57 games across three seasons.
We have a few more older examples in Alex Liddi and Carlos Peguero. Liddi actually reached AAA at 22, didn’t have a particular problem with strikeouts that year or the next, but suddenly developed a strikeout problem in his third attempt at AAA. For whatever reason that stuck. He had a career 38.8 K% in the majors in 61 games. Peguero was also in the Mariners’ system with Liddi at about the same time. He hit AAA at 24, had a 129 wRC+ with a 31.8 K% and 5.8 BB% thanks to a .434 BABIP. He got a sampling of games at the MLB level, the K/BB remained, the BABIP didn’t so he was bad. He repeated AAA, the walks improved, the strikeouts didn’t, and he then struck out in nearly half of his 57 PAs. He hung around for a while in that Quad A zone, but finished his career with a 39.5 K% in 319 career PAs.
Julio Carreras was a 49 wRC+ hitter in AAA so we can ignore him. Collin Delome was never a good hitter in AAA either, so we can also ignore him. And lastly Tommy Mendoca had a 41 wRC+ in AAA with his terrible K/BB numbers, so we can also ignore him.
As far as good comps, well honestly they’re usually younger than Baez currently is. Joey Gallo was. Franklin Barreto was. Greg Halman was. Jose Siri was older when he first reached AAA, as was Carlos Peguero. This list is both somewhat encouraging and very discouraging in the sense that I couldn’t find a good comp, but it sure seems like hitters with a 30% K rate strike out way too much to make it work in the MLB with almost literally the only exception being Joey Gallo. David Huff is a bad hitting catcher and Jose Siri is in the MLB for his defense. If Edwin Rios could play defense at all, he’d probably still keep getting chances, but he’s probably in that 90 wRC+ range too at best.
There is zero rush to promote him. The Cardinals do not have a hole in the outfield at the moment. And given the track record of prospects with a 30% K rate, not to mention the walks part, I don’t think it makes any sense to promote Baez right now. If you cannot make contact, it usually doesn’t matter how much power you have. And if you do not walk, it’s very difficult to overcome a low OBP as a hitter. I think Baez will improve, certainly with walks, and I think it makes sense to let him keep developing.
