MLB Prospects Breakout Watch for Fantasy Baseball - Matthew Liberatore, Nolan Jones, Brandon Pfaadt, Michael Busch and more

April 22, 2023

MLB prospects risers and fantasy baseball breakout rookies, based on minor league Statcast data for Week 4. These hitters and pitchers are excelling in AAA.

With the passing weeks, we get more and better data to use. This year, we have more and better data for all of AAA (that is the International League and the Pacific Coast League). With the International League adding in the Statcast infrastructure, we can now know a whole lot more about the players down there.

Enter this weekly post, in which I take a look every Thursday at the standout fantasy baseball prospects in AAA. I will try my best to keep the analysis to the players we could see in the Majors soon, and you will see that reflected here.

I am focused almost entirely on skill-based data. Things like launch velocity, launch angle, pitch velocity and movement, and more things of the like. I'm probably not even going to mention batting averages or ERAs. Those types of stats are random enough in the Majors, and they are downright useless to look at when you're talking about AAA. So let's talk about a few names to consider adding, or at least closely monitoring, in your fantasy leagues this week.

Prospect Pitchers

Brandon Pfaadt, Arizona Diamondbacks

There were some flirtations with Pfaadt making the Major League rotation out of camp, but he couldn't quite crack it. The Diamondbacks have been rolling with Madison Bumgarner once again, and it hasn't been going well. Not only are there on-field questions with Bumgarner, but we've heard some rumblings about off-the-field stuff there as well. Of course, we wish Bumgarner the best and we have had a blast watching his great career, but we have to focus on reality – and the reality is that it does not look like Bumgarner is long for a spot in the rotation.

The "Baby Snakes", as they have been nicknamed, are playing great baseball and currently sit in first place in the NL West. Think what you will about their chances of actually beating out the Dodgers over 162 games, but the truth is that it's a competitive ball club we're looking at and they have to be in win-now mode. That should facilitate the promotion of Brandon Pfaadt sooner rather than later.

Pfaadt was one of the standouts in the minor leagues last season, going for a ridiculous 26.9% K-BB% across 29 starts, mostly in the PCL which is the toughest league to pitch in in all of the minors. He struck out 218 hitters in 167 innings and walked only 33. Pristine stuff. Here is a quick look at this pitch mix, although we are talking about only three outings so far this year:

A good fastball and a great slider with a changeup and curveball in the mix as well. That is good to see, as we often hesitate about pitchers that do most of their work with the fastball. It is a lot tougher to get a fastball by a Major League hitter as compared to a minor leaguer, of course, so it's really important for these young pitchers to already have good secondaries – and it seems like Pfaadt had that.

I think he'll be up by the middle of May, and he very well could get the call as soon as next week.

Matthew Liberatore, St. Louis Cardinals

The Cardinals are desperate for help in the starting rotation, and the next man up for them would seem to be Liberatore. He's pitching phenomenally in the minors and the Cardinals currently hold a 4.64 team ERA which puts them in the bottom half of the league, and that's with the help of their strong bullpen.

Despite the tragic rotation, the Cardinals still have to be the favorite in the NL Central with their potent lineup and strong bullpen arms. I think they're probably already looking forward to trying out some new guys in the rotation. Here's what Liberatore has done so far this year:

A 17.6% SwStr% and a 1.9% Brl% are just fantastic. His 33% strikeout rate is the best in AAA, which is exactly what you want to see.

Pitchers tend to lose a few points in strikeout rate when being promoted to the Majors, but it is a relatively sticky statistic. On average, a pitcher's K% drops three points when going from AAA to the MLB. In Liberatore's case, that would put him at 30% and work just fine. He could even fall to 27% or so and still have a chance to be quite good for fantasy purposes.

The Cardinals need help, and Liberate is pitching well with a deep arsenal - he is right there with Pfaadt in terms of minor-league pitchers to stash.

Andrew Abbott, Cincinnati Reds

This is not a guy to add right now since he's in AA and probably not coming to the Majors soon, but I couldn't leave him out this week after seeing what he's done in two starts so far. So far in 2023, he has faced 35 batters and struck out 25 of them.

K% Leaders, AA-AAA

So yeah, we're talking about AA ball and a tiny sample – but it's not easy to post that high of a strikeout rate even over three innings. Keep an eye on Abbott, I'm definitely adding him in dynasty leagues if he's free.

Prospect Hitters

Nolan Jones, Colorado Rockies

Jones was strangely called up to the Majors for a few days only to not play at all and be sent back down a few days later. Weird stuff, Rockies!

Anyways, Jones has been terrorizing pitching in the Pacific Coast League so far this year with a league-leading 1.398 OPS. He's hit seven homers in 53 PAs while walking as often as he's struck out (seven times each). Jones has a great 14.3% Brl% and a 76% Contact%. Only 11 hitters have pulled that off in all of AAA. He has legit exit velocity (110 max, 107 90th percentile) and it's really encouraging to see him cut the strikeouts down, even if it's just in the minors. For comparison's sake, he had a 26% K% in AAA last year, so there is real improvement here so far.

The Rockies are a bad, bad Major League team. They could seem to benefit from an upside bat, and they should be wanting to see what they have with Jones who was acquired this offseason. I'd pick him up in deeper leagues when he gets another call.

Michael Busch, Los Angeles Dodgers

Busch is another one of those 11 hitters I mentioned above in the Jones' write-up. He has a 10.9% Brl% and an 80% Contact% in 73 PAs so far. That is an elite combination. He is one of only three hitters with a 10%+ Brl% and an 80%+ Contact% (Miguel Andujar and Dominic Canzone being the others).

Busch is currently listed as the Dodgers' #3 overall prospect, and for once, their Major League lineup isn't completely loaded. They could actually use a boost in the middle infield after losing Trea Turner to free agency and Gavin Lux to injury. Keep an eye on Busch, and grab him as soon as he gets the call to the show – or sooner!

Ronny Mauricio, New York Mets

The Mets have already called up Francisco Alvarez and Brett Baty, so why not make it a trio of top prospects by promoting Mauricio soon?

He is certainly banging down the door with a 1.193 OPS in the minors, and the quality of contact has been terrific as well with a 13% Brl% and a strong 76% contact rate.

It's not exactly clear where Mauricio would play for the Metropolitans. His primary position is shortstop, and the Mets are obviously not hurting there. He might need an injury to happen to find himself regular PAs in the Majors, but if that does happen - he's someone to have a look at.

That's it for this week looking at Statcast data down on the farm. Check back next week for more updates!

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