Ron Marinaccio is featuring his fastball and looks nastier than ever

Despite surrendering a couple of walks on Wednesday’s outing, Ron Marinaccio threw a crucial scoreless inning against the Cleveland Guardians in which he struck out two hitters. To finish his outing, he fooled Andrés Giménez with a beautiful changeup on the inner side of the plate.

However, we are not here to talk about Marinaccio’s changeup, which is probably his main out pitch. We are here to discuss how his fastball is becoming more and more important in his repertoire at the expense of the cambio and the sweeper.

Let’s start with the obvious: Marinaccio has been a beast so far. Yes, we know that the sample size is tiny and the season is just a couple weeks old, but he has a 1.50 ERA and 11 strikeouts in 6 innings of work, and opponents are hitting just .100 off of his heater. That’s very hard to ignore.

The right-hander was already stellar in 2022, with a 2.05 ERA in 44 innings with the Yankees. Still, you can always be better, and Marinaccio sure looks improved.

Last year, he used his four-seamer 44.3 percent of the time, the changeup checked in at 37.9 percent, and the sweeper at 17.8 percent. Marinaccio has taken a fastball-heavy approach this year, increasing its usage to 61.5 percent while lowering the frequency of the changeup (31.9 percent) and the sweeper (6.6 percent).

Note: Pitch usage data does not include yesterday’s game.

While Marinaccio’s fastball has been a bit slower this season than last (93.5 mph on average compared to 94.6 mph in 2022), it has been much more effective. The velo decrease probably has to do with the fact it’s still early. It will probably creep closer to last yea’sr levels and it was mostly 94-95 on Wednesday’s outing.

This year, the pitch is earning a 31.4-percent whiff rate, which is incredible for a fastball. It’s also up from 26.3 percent last year. It’s also generating a lower xwOBA (.226) in 2023 than last season’s .320. Again, it’s probably too early for some of these changes to stick to their current levels, but they are noteworthy nonetheless.

Seeing the results that Marinaccio has gotten with the fastball in the early going, it’s no wonder he has been using it so much. The pitch movement profile has also changed, and it looks nastier than ever.

Last year, Marinaccio’s heater already had elite run, 45-percent better than his peers. This campaign, it has 14.5 inches of arm side run, or a whopping 72-percent more relative to the league average.

Just look at where the pitch is usually intended:

Baseball Savant

Good luck hitting 95 mph-fastballs with that kind of movement and located near the hands (for right-handed hitters), or while the ball goes away if you are a lefty.

This video is from yesterday, in an at-bat against Josh Naylor:

And here is one from last year:

The difference may not seem huge for some, but believe us, it’s noticeable for hitters — very much so.

As it usually happens with Marinaccio, he will give away a free pass here or there. In fact, he’s been a bit more wild in the first couple weeks with a 17.3-percent walk rate. But he’s also striking out 47.8 percent of batters out of the 23 so far. So yeah, that will do.

Last year, Marinaccio’s fastball-changeup split was much closer, and he threw way more sweepers. This year, the pitch mix has changed, and he is featuring the heater a lot. There is a reason for that, and it’s simple: it’s a nasty pitch.