Ottavino hasn't allowed a run in 35 straight outings dating back to Sept. 6, 2014, eight months before he underwent Tommy John surgery. He returned to the big league roster on July 5.
"It feels good, especially coming back off surgery and not knowing, not expecting to give up any runs for a little while," Ottavino said. "I figured that was just a nice run I was on last year before I got hurt."
This year, Ottavino has surrendered just 10 hits in 15 innings scattered over 19 outings. Opposing batters are hitting just .189 against him -- and are 2-for-20 against his slider.
Against right-handed batters, he has mastered his approach from the third-base side of the rubber, which -- coupled with his 6-foot-5, 220-pound frame -- creates a deception as the pitch slides into the strike zone.
"Those are very difficult angles to deal with as a hitter," manager Walt Weiss said. "On top of the deception and the high front side and the elbows and knees coming at you, there's just a lot going on there that a hitter has to deal with."
In Monday's win, Ottavino struck out Trea Turner on that slider, then fooled Jayson Werth with it for a called strike two before he forced a groundout to end the game. Ottavino's slider is averaging 2,737 rpm -- the ninth-highest spin among sliders for pitchers who've thrown it at least 50 times, according to Statcast™.
At altitude, a spin rate that high for a pitch that effective isn't necessarily common.
"I just think [in Colorado], you just can't expect to have a ton of break," Ottavino said. "So you have to kind of try to make your slider or breaking ball, in general, look as much like a fastball as possible. That way, when it does bite, it's effective because it fools the hitter. If you just try to rely on too much movement, you might not end up really getting what you want."
Ottavino supplements his slider with a changeup and a two-seamer that hasn't reached his personal high of 97 mph, but he has shown increased velocity since his return, Weiss said.
The six-year veteran regained the closer role one month after returning to the big league roster, largely due to the struggles of Jake McGee and Carlos Estevez, who blew consecutive ninth-inning leads earlier this month.
Earlier in his career, Weiss didn't trust Ottavino in such crucial situations, particularly due to his inability to hold runners. But Ottavino's hurried approach and his improvement against left-handed batters -- usual suspects as ninth-inning pinch-hitters -- has given Weiss conviction.
"There's a lot of savvy there," Weiss said. "His intellect, his ability to made adjustments has been critical."
"I just relish pitching with the game on the line, no matter when it is," Ottavino said. "I really like to pitch no matter what. I'll pitch in a blowout, but I get antsy when the game is on the line, I want to be the guy out there."