The 25-year-old hasn't allowed a run over his past three appearances while striking out three and walking just one. He is starting to be used in more high-leverage situations and earned his first victory of the season on Saturday with a clean seventh inning vs. the Orioles.
"It was a great opportunity for me," Jeffress said. "I knew a couple of relievers [weren't available] and I would probably get an opportunity to pitch. It was a great opportunity for me and I was glad for him to trust me in that situation."
There's never been any doubt about Jeffress' natural abilities on the mound. He consistently records upper-90s velocity on his fastball, but his weakness has always been a lack of command.
The sample size is still incredibly small, but even dating back to his season with Triple-A Buffalo, pitches in the zone have been a lot more consistent. He credits most of that to a new three-quarters arm slot this season, compared to previous years when he threw more over the top.
"I think it has gotten pretty good results," Jeffress said. "It has been staying down in the zone, working for the past month or so and just attacking with my best stuff has been working pretty good.
"If you command the ball in the game, you'll get hitters out. I'm just trying to put it where it needs to be and pitch with a little conviction."
Gregor Chisholm is a reporter for MLB.com. Read his blog, North of the Border, and follow him on Twitter @gregorMLB. This story was not subject to the approval of Major League Baseball or its clubs.