TORONTO -- Justin Miller turned 31 on Wednesday. He celebrated with 1 2/3 scoreless innings against the Yankees and four strikeouts, which included fanning the side in the sixth inning and earning the win. These kinds of outings have become typical for Miller, perhaps the Nationals' most impressive and obscure find after he didn't appear in the Majors in 2017 and posted a 5.48 ERA for Triple-A Salt Lake in the Angels' Minor League system.
Miller began the season at Triple-A Syracuse, where he did not allow a run in 13 2/3 innings with 23 strikeouts and three walks. That earned him a promotion to Washington, where he has made eight appearances and not allowed a run in 10 2/3 innings. He has struck out 21 batters without issuing a walk.
Miller has only surrendered two hits -- a double to the Yankees' Greg Bird on Wednesday and an infield single on a quick pitch to the Orioles' Mark Trumbo on May 29 -- while holding opposing hitters to a slash line of .061/.059/.091. That adds up to a remarkable minus-0.84 Fielding Independent Pitching.
"Honestly, I don't know how we got him," manager Dave Martinez said after Wednesday's game. "But I'm glad he's here."

Before this season, Miller was a journeyman reliever, bouncing around with four previous teams and posting a 4.99 career ERA in 82 games in the Majors from 2014-16. He struggled in Triple-A last season and never cracked the Angels' Major League bullpen.
So just how did Miller transform into such a dominant weapon out of the Nationals' bullpen this season?
Miller is not throwing any new pitches, mixing the same fastball-slider combo he's always had, and at about the same rate he has always thrown it. Nor has his velocity increased since his last stint in the Majors. Yet, when the Nationals scouted him during the winter, they quickly signed him to a Minor League deal before he could showcase for other teams. General manager Mike Rizzo loved the way Miller was not afraid to attack hitters in the strike zone and thought his arsenal could have success in the big leagues.
"The stuff is there," Rizzo said. "I think the stuff ticked up this year, but I think his mentality, the mental side of it, ticked up. He's an aggressive dude who comes at you and trusts his stuff, and he's not afraid."

The Nats' scouts liked everything they saw. However, they wanted to make one small tweak to his delivery.
Miller had always thrown from a bit of a closed stance since his days in junior college. But this season, his delivery is even more closed off. In his set position, his left foot is even closer to the third-base bag than before.
 "I think it's deception," Martinez said. "I kind of wanted to see it from a hitter's angle, what he does, he's got his back turned toward you. As a right-handed hitter, the ball comes out of nowhere."
That deception is a big reason why Miller has been unafraid to pitch almost exclusively in the strike zone. Of the 507 pitchers who had thrown at least 100 pitches this season, entering Thursday, no one was throwing more strikes than Miller at 59.5 percent. And batters are swinging at his pitches inside the strike zone less frequently (58 percent in 2018, compared to 70 percent in '16) and chasing pitches outside the zone more frequently (37 percent in '18 to 22 percent in '16).

To remain more consistent with his delivery, Miller started playing catch with a heavier 10-ounce baseball before games at Triple-A Syracuse, instead of a standard five-ounce baseball. The heavier ball helps him keep the same arm path, loosens up his arm and allows him to focus on maintaining his footwork.
"I would probably say that makes me more consistent of what I've had this year," Miller said.
Whether Miller's success is sustainable remains to be seen. But he has already started to gain the trust of his manager and has started to see increased chances to pitch in high-leverage situations. It has been the sort of boost the Nationals' bullpen needed from an incredible under-the-radar find during the offseason.
"You can use him in different situations, high-leverage situations, and it doesn't faze him a bit," Martinez said. "You can do a lot of things with him, multiple innings, he takes the ball every day."