The D-backs right-hander, who had a streak of four consecutive scoreless outings earlier this year, has not allowed a run in his past five games, a span of 4 2/3 innings.
"He's being more efficient with his pitches and keeping his delivery under control," D-backs manager A.J. Hinch said. "He's kind of a hyper guy to begin with, and he really tried to explode at the end of his delivery, and when he does that his pitches elevate and out over the plate, and it gets him in trouble. He's just been more aggressive in the strike zone."
Those are the physical aspects of his turnaround, but there is a mental part as well that could be even more key to determining whether or not Vasquez can keep it going.
"His stuff is good enough, and for a young reliever it's hard to believe that until you've felt it for a while," Hinch said. "Every time he takes two steps forward, he takes one back. It's the evolution of a reliever with good stuff that's trying to solidify himself in the big leagues. I have a lot of belief and a lot of trust in him, and I hope that he's starting to get the confidence needed to put these strings together."