"It's not the 95 or 96 [mph] like I'd like it to be yet," Masterson said. "Hopefully that's what we're working on. And then we made an adjustment. We were flying open quite a bit the last couple outings. My arm feels great. The movement is great. The slider is great. It's more we were kind of flying, so now going into [Friday], we did a little bit better of staying behind it.
"We were behind the ball [Friday], so maybe velocity will come after that. But the sinker has been 90-91 [mph]. Yeah, some go down, but that's the way it always is with me. I get a range. But, yeah, we haven't been able to step on the gas pedal for those other ones. If we keep doing what I did [Friday], I'm not too worried about it."
During Friday's 3-2 loss to the Blue Jays, Masterson was charged with two runs -- one scored after he exited the contest -- on six hits in 6 1/3 innings. The right-hander ended with nine strikeouts and two walks for the Tribe. In his previous two outings, Masterson allowed 12 runs (10 earned) on 14 hits with 11 strikeouts and eight walks in 8 1/3 innings combined.
According to Fangraphs.com, which uses PITCHf/x data, Masterson has averaged 88.7 mph on his fastball this season. Last year, the righty averaged 93.95 mph in April and 91.6 mph for the season. He averaged 91.9 mph in 2012 and 92.7 mph in '11.
"He looked better," Callaway said of Masterson's outing on Friday. "And his [velocity] was up from where it has been. Now he just has to continue with those mechanics and build his arm strength."
Jordan Bastian is a reporter for MLB.com. Read his blog, Major League Bastian, and follow him on Twitter @MLBastian. This story was not subject to the approval of Major League Baseball or its clubs.