When looking through the minor leagues, one of the worst habits you can develop is looking too much at a player’s numbers. There are many factors that can play into some of the base numbers to be misleading.
Between the defense behind him, or even his age relative to the rest of the league he’s playing in, numbers don’t always tell the story.
That’s what makes right-handed pitcher Oliver Mateo one of the most intriguing relief prospects in the Pittsburgh Pirates system. Even his numbers can lead you to being torn on what kind of upside the righty has.
On one hand the walks and ERA are bad enough to send you running for the hills, while on the other Mateo struck out 82 batters in just 37.2 innings pitched in 2021 for the Bradenton Marauders.
The 24-year-old Mateo struck out an absurd amount of hitters, but also walked more than a batter per inning, finishing with 40 on the season.
Mateo offers an explosive fastball that has late, tailing action and can dial the pitch up to triple digits in a pinch. He pairs that with a nasty wipeout slider that lands in the mid-to-upper-80s.
At their core, they are two of the better pitches in the Pirates system, and it was recognized at the end of the year, as the Low-A Southeast managers voted that Mateo possessed the best fastball and slider in the league through Baseball America.
It’s special enough to get recognized to have one of the best pitches among your peers, Mateo had two.
Armed with two of the best pitches in the Low-A Southeast, Mateo struck out more than two batters per inning, and held opponents to a .135 average and .582 OPS.
The clip above includes three of those five outings for Mateo and shows a good indicator of what kind of pitcher he is.
Mateo does seem to have a better feel for his slider than his fastball, in which he is able to locate all throughout the strike zone. While Mateo doesn’t throw a changeup, he does use his slider as a backdoor pitch to get called strikes against lefties in almost the same manner you would normally see out of an off-speed pitch.
While he can dial it up to triple digits, which was more prevalent earlier in the season, you can see him bring it back to a more controlled 94-96 while in the strike zone in these clips. In the same at-bat he was still able to go back into the upper 90s to try and get the strikeout and was even able to hit 98 on the corner for a strike.
In the last outing that was showed, Mateo faced off against two former first round picks from the Minnesota Twins, Aaron Sabato and Keoni Cavaco, and struck them out with ease. Sabato is a former college bat from North Carolina who hit 19 home runs in 2021, and Mateo fooled him pretty good on the first pitch slider.
The future for Mateo will depend on how much progress he can make with his control. If he gets it under control, he easily has the stuff to pitch at the back end of the major league bullpen.
However, you would have to imagine he doesn’t make it too much further if the control doesn’t improve. Despite the strong finish to the season, he still walked 23 batters in 24.2 innings. So, even at his absolute best, the control was still a major issue.
Mateo is the definition of a boom or bust prospect. There have been plenty of players who flamed out at the A-ball level with those kind of walk numbers. On the other side, those strikeouts make you want to hang on as long as possible.
Due to his age and being a reliever, Mateo won’t likely ever make it too far up any prospect list, but the righty will certainly be a player to watch come 2022. He could very well end up being a pitcher in the back end of a bullpen, or he may never even reach Altoona. Either way, this upcoming season will be a big indication on the path he may take.
This Week on Pirates Prospects
Anthony began writing over 10 years ago, starting a personal blog to cover the 2011 MLB draft, where the Pirates selected first overall. After bouncing around many websites covering hockey, he refocused his attention to baseball, his first love when it comes to sports. He eventually found himself here at Pirates Prospects in late 2021, where he covers the team’s four full season minor league affiliates.