A quick rundown on the top ranked Royals pitching prospects through the prism of K% and BB%.
Just for context, a K% of 18.5% is average. 20% is above average, 22.5% is great and 25% is elite. K% is important because it tells you not just if a guy gets a lot of strikeouts, which is great, but if he strikes out a high percentage of batters rather than giving up lots of hits and walks.
For BB%, 8.5% is average, 7% is above average, and anything under 5% is elite. 9% is roughly the success fail line if you have an above average K%. Anything over 10% is awful and will likely lead to trouble unless your K% is well over 25%.
Yordano Ventura (AA, AAA)
AAA - K's = 36 of 155 BF (23%). BB% = 17 of 155 batters (11%) The silver lining here is that last year in his debut at AA his walk rate jumped from 8.5% at high A (an average number) to 10.5% (awful). In that time his K% was only 20.3%. He got that number down this year from 10.5% to 8.6%, while his K% was 32% (74 of 230). I think he should finish the season at AAA and start next year there, too, to make sure his walk rate doesn't stay up and to see if his K% jumps back to the elite level.
Kyle Zimmer (A+, AA)
A+ - K% = 113 of 379 (29.8%). BB% = 31 of 379 (8.1%). Absurd K%, just slightly above average BB%.
AA - K% = 19 of 47 (40.4%) small sample size. BB% = 3 of 47 (6.3%). small sample size.
Zimmer's numbers this year are incredible bordering on absurd. The fact that his control was a bit above average while his K% was well past elite is HUGE. He should still finish up the year at NWA, but next spring he will be in Omaha and could be in KC by June if this continues.
Kyle Smith (A+)
He's getting K's on 21.9% of batters faced (90 of 410). He's only walking 6.8%, which is above average. I know there are concerns about his stuff being able to play at higher levels, but that's why I think he needs to move up. If his stuff won't play at higher levels, he needs to move up and flame out, because there's no reason to keep a guy that can miss bats and has above average control at the A+ level.
Jason Adam (AA)
Last year his K% was 18.9%, all at Wilmington. This year its 19.1%, all at NWA. A modest bump, but nothing to write home about. Still, those are roughly average, slightly above average numbers. His walk rate last year was 5.5%. This year it has jumped to 9.1%. That's a red flag for the local kid. If those walk numbers don't come down significantly (around 8% is probably his success/fail line since he's not an elite strikeout pitcher), he's going to stall out in his rise through the system.
Bryan Brickhouse (A)
He's striking out 19.3% of batters in the Sally. Last year, that number was at 17.3% in the midwest league (10 starts). His walk rate of 8.3% is just a tick above average. Unfortunately, he's joined the TJ brigade for the Royals, so we probably won't see him again until next August
Brooks Pounders (AA)
He's always been an interesting prospect to me. Strikes out 19.6% in the Texas League. Walks 8.1%. Both are acceptable rates. I have a feeling he's going to be a major league average pitcher. Nothing more, but if he's the Royals 5th starter in a couple of years, their rotation will probably be strong. If he's their #2 starter, that's probably trouble.
Christian Binford (A)
Last year at Burlington (rookie) he struck out 18.7% (31 of 165) of batters while walking 2.4% (4 of 165). That is not a typo. That's two point four percent of batters walked. This year in the Sally he's struck out 111 of 439 faced, or 25.2%. Yet his control has remained exceptional, walking just 20 (4.5%). I don't know if he's a prospect, but he's not that old (still just 20) and those numbers suggest that he's at least someone to keep an eye on.
Miguel Almonte (A)
In the Sally his K% is 24.6% (102 of 414). BB% is 7.9% (33 of 414). He's been a little more hittable this year than in the past, but he has had very good control throughout his career, so I'd say he's actually fulfilled the expectations after bursting onto the scene last year.
Aroni Nina (A)
K% in the Sally is 19.6% (60 of 305). BB% is 12.1% (37 of 305). Obviously, that walk number is much too high, but walks have always been a problem for Nina (career BB/9 of 5.3). He gives up less than a hit an inning, but if he can't locate, he won't make it to AA.
Chris Dwyer (AAA)
16.8% K's, 8.9% walks. That basically captures Dwyer's problems. He doesn't strike out nearly enough to have merely average control. Looking back to his last good year (2010) his K% dropped from 25% at A+ to 20% the next season at AA. He's always had problems with walks, but once his elite K% (25% to 20%, 16.8%, 16.8%) evaporated at higher levels, the walks buried him.
Sam Selman (A+)
20.6% K's, 15.6% walks at Wilmington. A walk rate like that will have him out of baseball in three years. Last year his control was much better (9% BB), but he threw 5 WP last year and has 10 this season. If Selman is to advance, it will be because he gets something resembling below average control.
Colin Rodgers (A)
17.4% K's, 11.1% walks. He's still quite young, but he hasn't shown the ability to have elite K's (only 12.6% last year in rookie ball) and his walk rate is far from exceptional. I haven't seen him throw, so maybe cleaning up his mechanics will help, but I don't see much upside here quite yet.
Daniel Stumpf (A)
21.8% K's, 9.8% walks (425 batters faced). I am taking a wait-and-see approach with Stumpf. His numbers aren't elite, but he could be a horse in the rotation. If his control is about average (basically just trim about one walk every other start), he could be an innings eating mid rotation guy, provided he maintains his K% and remains tough to hit overall (only 81 hits in over 100 innings).
This exercise has shown two things. First, the Royals potentially have two very good starting pitchers in the upper levels. Zimmer can be an ace if he continues to progress. Ventura can be a very, very good #2 if his development follows the same pattern as it did after his last promotion.
Second, the Royals have a lot of talent at the A level. Almonte, Binford and Stumpf should all be in the Carolina League next year. Almonte profiles as a 2/3 guy, while Binford and Stumpf could fill out the back of the rotation.
This doesn't even take into account a guy like Kyle Smith, who has been very good at A+.
Bonus numbers -
K% - 22.3%. BB% - 10.6%. 179 batters faced.
Those are Danny Duffy's AAA numbers this year. He's not quite back yet. Control is the last thing to return, so perhaps by mid August he will be ready.