Oviedo boosts his slider with help from a new pitch

Johan Oviedo got something with his slider Friday that he had been missing his last couple times out: Called strikes.

The slider is Oviedo's best and most-used pitch, and he has the ability to move it around the strike zone or have it fall out for chases. However, hitters seemed to be on it of late, swinging at it more often and just watching 14 go by for strikes over his last three outings combined.

That's what made his six innings of one-run ball in the Pirates' 13-3 win over the Diamondbacks Friday interesting. His slider was the key pitch, but instead of chasing, hitters watched it go by for a dozen called strikes. Oviedo would go on to strike out seven, all of them with the slider:

"A lot of take with the slider today," Oviedo said. "I haven’t been able to get it like that in a while."

He has a theory for why that happened: "People were backing out because of how well the sinker played."

The sinker has been a project for Oviedo these past two offseasons and something he teased during spring training. It was placed on the back burner when he got off to a good start, though, and he started to rely on his slider more and more, throwing it more often than his four-seam fastball, even. He allowed just six earned runs over his first four starts, lengthening the Pirates' rotation.

The next four starts were a complete reversal of fortunes. Oviedo allowed three times as many earned runs (18) and did not have a single quality start. Among the main problems was the slider. In those first four starts, hitters whiffed at 34.3% of the sliders they swung at and mustered just a .339 slugging percentage and .292 wOBA.. In the previous four starts, that whiff rate fell to 21.4%, while the slugging percentage rose to .480 and the wOBA to .394.

Meanwhile, hitters had a .421 batting average in the month of May against his four-seam fastball. It wasn't performing like a putaway pitch, and with hitters sitting on the slider more, Oviedo started to struggle.

Oviedo was looking for a change. It was about this time a year ago that Mitch Keller, a fellow young starter with stuff and inconsistent results, turned to the sinker to jumpstart his career.

"Seeing how good it worked for him," Oviedo asked himself, "why not give it a chance?"

It worked Friday. MLB's pitch tracking registered all of Oviedo's fastballs as four-seamers, as new pitches are not always picked up by their system. However, looking at individual pitches' spin and vertical movement, it does look like Oviedo had two distinct types of fastballs, ranging from getting 15 inches of drop to 23.

Derek Shelton said the key for Oviedo was that he stayed in attack mode, especially with his fastballs. While Oviedo still threw 48 sliders on his 96 pitches (50%), he had a better pitch to help set it up.

"Tonight, he had better command of his fastball and then the slider was better," Shelton said. "There was more consistency to the arm slot. There was more consistency to the action of the pitch, which we had not seen over the last two starts.”

Sinkers and sliders are a common pairing throughout the league because the two pitches tend to tunnel off of each other. Oviedo has always had a plus slider, but being able to throw a pitch that looks similar to it out of the hand and comes in at 96-98 mph like the sinker is a way to keep hitters honest.

The reason Oviedo made the change now is because he knows it's a long season, and he felt he needed that new look.

"If you can bring something new, different that can work to get a different swing, especially ground balls that we need," Oviedo said. "In some situations where you need a double play or something like that, getting people a little bit away from my slider. That was kind of like the plan. A lot of people were chasing my slider in a lot of situations. Try to get that sinker in and try to take people a little bit off."

Oviedo couldn't pinpoint postgame exactly how many of his fastballs were sinkers and how many were four-seamers. He just knew he had a mix.

And really, that's all the matters.

"It worked," he said. "That’s all I care about."