An investigation into why Felipe Rivero is slumping

Pittsburgh Pirates RP Felipe Rivero is in a mini-slump. It was bound to happen eventually.

And by mini-slump, I do mean “mini.” On August 2, the previously invincible Pittsburgh Pirates reliever gave up a bloop and a blast. On the sixth, he ran out of gas trying to complete a four out save. On the 10th, he allowed two inherited runners to score. This is probably an overreaction, but three shaky outings in an eight day stretch will raise eyebrows. It’s worth a closer look.

The first instinct is he is overworked. The second, third and fourth instinct is he is overworked. It’s a reasonable assumption. He’s throwing more innings and harder this year than he has in any previous season. That would wear anybody down.

Rivero shrugged off the idea he was tired during a presser on Tuesday. Hurdle did too. “Trust a man when he tells you he feels good,” Hurdle said. “By the show of velocity and stuff tonight, he looked good.”

So if it isn’t fatigue, what should we take away from Rivero’s slow start to August?

MECHANICS

My first instinct when Rivero goes a little haywire is to look at his follow through. I wrote for The Point of Pittsburgh in May that the biggest change for him between his time with the Nationals and now is where he lands. With Washington, he took a step to either first or third base. In Pittsburgh, he takes a step towards home. He’s not wasting momentum anymore, which is why he can throw 102 now.

So let’s look at the tape of the pitches of the defining at-bat of all three games so far. Where is his momentum taking him?

There may have been a mini step towards first on Martinez’s double, but that could be just the camera angle. Besides that, the follow through looks fine.

The same can be said for his release point. It may look a little inconsistent, but that’s fairly normal. There isn’t a clear outlier in the recent slump.

So if there is a mechanical problem, it’s not a glaring issue or a quick fix.

THE PITCHES

Rivero has thrown 885 pitches this year, the majority being fastballs (roughly 63.6%, according to Baseball Savant). There’s no shock there. His outing on the sixth was a bit overkill, though, throwing 32 heaters on the 40 pitches Statcast registered, including his last 11. There was a clear drop in velocity that day too, with him starting at over 100 MPH and ending at 95. Besides that, his heater is still close to triple digits with his change and slider staying steady too.

If you look at his three “poor” performances, the mix of hard and offspeed stuff is about the same…

…and the movement is fine too. His heater isn’t moving as much as it was during its peak and the changeup is a tad flat, but it’s still within the parameters he has set this season.

The location has been iffy, though, especially against the Padres Sunday. Whether he was having a bad day or was just pitching to contact because he was tired, he offered a lot of pitches down the middle.

Adam Duvall’s home run on the second was also right down the pipe. A pitcher can get away with some mistakes, but eventually he’ll pay. He’s paying right now.

APPROACH

Like I mentioned, Rivero has thrown a few more fastballs than normal lately, but I would be remiss if I didn’t see if he’s throwing different pitches in different counts. Here he is from opening day to August 1:

And from August 2 on:

Again, it’s fastball heavy and a very small sample size, but throwing some breaking stuff when he’s behind in the count would probably help.

But that’s not what I want to talk about with his approach. If you have ever heard a Hurdle postgame press conference, you have heard him talk about first pitch strikes. It’s the M.O. of all Pirate pitchers, and Rivero is no exception. Surprisingly, this is actually one of the few things Rivero is not elite at yet. He throws first pitch strikes at a 55.4% clip this year. While that sounds good, it’s 16th out of the 21 pitchers the Pirates have used.

When Rivero is up 0-1, the batter may as well cut out the middleman and take a seat. Only one in ten batters will reach base when they fall behind in the count on the first pitch. When Rivero is down 1-0, batters have a prayer. Sure, their .167/.293/.262 line is still pathetic, but there at least is an opportunity to produce.

During the games on the second, sixth and 10th, Rivero was up in the count 0-1 seven times and behind 1-0 seven times. When he was ahead, batters went 1-7 with a single. When he was behind, they went 3-5 with a home run, double and two walks. Finally, we found a red flag.

But what did “Nightmare” take away from his recent clunkers? During his presser Tuesday, he said felt he was “going too quick” on the sixth, and that’s what threw him off. He’s trying to take it easier now. Since then, batters are just 1-6 against him, so that may just be the fix he needed.

CONCLUSION

So what did we learn, boys and girls? Well, not much actually. Mechanically, Rivero seems sound, which is good. His pitch selection is a little out of whack, but that’s probably due to a small sample size. He’d be better off throwing more first pitch strikes, but then again, who wouldn’t?

Honestly, if it isn’t fatigue- which neither he nor Hurdle thinks it is- this is probably just a stretch of rotten luck. A regression to the mean where his ERA winds up one-point-something. The horror.

The home run he allowed Duvall was a changeup, and he was one of the best changeup hitters in baseball last year. The Padres were pesky, strung together some long at-bats early and tired him out. Victor Martinez doubled, and that was all the Tigers got.

I wouldn’t put a lot of stock into this slump just yet.

Photo credit Daniel Decker