Twins manager Paul Molitor was most impressed by both pitchers' fastball command, as it allowed them to get ahead. Duffey threw 38 of his 58 pitches for strikes, while Mejia was 45 of 66.
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"I think what [Duffey] settled into was good fastball command -- anyone who throws 60 pitches in five innings is pitching ahead," Molitor said. "[Mejia] was rearing back today and letting it loose. He kept challenging people with that fastball but threw enough offspeed pitches. I have no complaints about his day, either."
Duffey lowered his ERA to 3.86 with his third straight solid outing, and he said he's focused more on results this spring after not making the Opening Day roster in 2016 as he tried to work on his changeup. He feels like it has improved enough to be a dependable third pitch, while he's worked on his glove-side fastball location in bullpen sessions.
"I'm not working on things in the game anymore," Duffey said. "I'm going out there to get outs. I feel good with where I'm at. I feel like everything is clicking right now."
Mejia, ranked as the club's No. 8 prospect by MLBPipeline.com, has impressed throughout camp with a 1.88 ERA. The big lefty has legit stuff, sitting at 94-95 mph on Monday to go along with his changeup, slider and curveball. He was considered a long shot entering camp, but he has thrust himself into the competition, earning praise from the coaching staff and scouts.
"It's going great," Mejia said. "It's all about getting the job done, and I think I've been doing that so far. I'm not getting caught up in who's doing what or what's being said about me."
The Twins, though, must decide what role Duffey, 26, will serve if he doesn't make the rotation, as he's also a candidate to be moved to the bullpen instead of heading to Triple-A Rochester as a starter. But Mejia, 23, is expected to remain a starter at Triple-A, even if he doesn't make the team.
"I think [Duffey] is in the competition for the team," Molitor said. "It depends on how much we think we need length there. I like the idea of having a couple guys with length, especially early if we go with a seven-man bullpen. We have roster questions to look at going forward."