MINNEAPOLIS -- The most valuable addition to Nathan Eovaldi's arsenal received some needed tweaks last month, as the right-hander fiddled with his grip and tried to add some diving action to a splitter that seemed to be behaving more like a knuckleball.
There was time to consider it after being sent to the showers after two-thirds of an inning on June 16 at Miami, which he hopes will be his final early exit. Eovaldi pitched into the ninth inning for the first time in his career on Sunday, earning the victory in the Yankees' 7-2 win over the Twins at Target Field.
"I would imagine it's just the split; I've been able to control it a lot better against both lefties and righties," Eovaldi said. "Throwing it for strikes too, not just swing and misses -- I feel like that's one of the big reasons I'm having success."
Eovaldi was on his game early, striking out four of the first six hitters, and he limited the Twins to just three hits through the first six innings. Slightly amped about the prospect of a complete game, his day finished on his 100th pitch, a slider that Miguel Sano whacked into left field for a double leading off the ninth.
"He was almost able to give our bullpen a whole day off, which was really nice as we move forward," Yankees manager Joe Girardi said. "We've got seven more games in a row. I thought it was great. I think he's improved all year."
It was, in Eovaldi's estimation, the best start that he has turned in all season. Catcher Brian McCann didn't disagree, and he said that the reason is the growing confidence in the splitter, a pitch that Eovaldi didn't even try until his final two starts in a Marlins uniform.
They worked it in sparingly early in the season, and McCann has no issue calling for the pitch now. According to Brooks Baseball, Eovaldi used it 21 times on Sunday, and McCann said that he has shown the ability to throw it for strikes both ahead and behind in the count.
"It's taken his game to another level," McCann said. "It gets hitters off the fastball and gives him another pitch. It's turned into a way above-average pitch."
Coming into Sunday, Eovaldi led the Majors with an average fastball velocity of 96.1 mph according to Fangraphs, but he needed another pitch to get hitters off his heater. Chase Headley faced Eovaldi while playing for the Padres and said that he recognizes the development that has taken place from the hurler's days in Miami.
"He's one of those guys that had a tremendous arm, but you could really sit on the hard stuff because you knew you were going to get a fastball, and at some point in the at-bat you were going to get a good fastball to hit," Headley said.
That's not necessarily the case anymore, as McCann said that hitters can no longer count on a fastball-slider-curve trio, a maturation process that is playing out right before the Yankees' eyes.
"The split-finger's not an easy pitch to hit, and it's not the easiest to throw either," McCann said. "For him to learn it this year and to be able to throw it like he's been doing is very impressive."
Bryan Hoch is a reporter for MLB.com. Follow him on Twitter @bryanhoch, on Facebook and read his MLBlog, Bombers Beat. This story was not subject to the approval of Major League Baseball or its clubs.