"It just looks like he's playing catch, and the ball's screaming in there," Melvin said. "I think that's part of what makes him so good, too, is it's an easy motion, and then all of a sudden the ball jumps on you."
"You watch him throw a bullpen," A's Minor League pitching coordinator Gil Patterson said, "and it's the same way you and I would go play catch with a beach ball."
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Patterson often kept A's Minor League pitching rehab coordinator Craig Lefferts company when Montas threw bullpen sessions during his rehab from a rib injury last summer, the two continually in awe of the right-hander's habit of maintaining 92 mph even when throwing at a 70 percent effort level.
At full go, Montas can reach back for 102 mph, as he did during an exceptional Arizona Fall League stint. Montas recorded a 0.53 ERA in 17 innings to help Mesa earn the AFL title.
"It was good just to pitch again and make up for all the time I missed and compete with a lot of good players there," Montas said. "I was feeling really, really good. My arm felt great. My rib was feeling really good. I feel like that was when I finally was able to know I'm 100 percent."
Montas was sidelined nearly four months after undergoing February surgery to remove his first right rib, before he injured a second one while rehabbing at the Triple-A level, delaying his return.
"It was really painful," Montas said. "If I made a quick move, it would feel like somebody just shot me in my chest. Sometimes, I couldn't take a deep breath."
Though there's thought Montas would be better utilized out of the bullpen, the A's will keep him on a starter's schedule this spring.
"I've done both before, so I feel comfortable doing both," said Montas, who appeared in seven games for the White Sox in his 2015 big league debut. "I always feel like it doesn't matter if I'm starting or reliever. The job is still to go out there and get outs. That's what matters. I don't have a preference. I just like to pitch."
Montas, who will be 24 in March, is equipped with a slider and cutter that Patterson called "electric." His slider, Patterson noted, has great depth, while his cutter is hard and late. His changeup, typically clocked at 90 mph, is a work in progress.
"The only thing we made him do was throw his changeup," Patterson said. "I don't want to put him in a position to fail, but I also know you have to be in a position to be a complete pitcher, and even with throwing 100 you still have to pitch, you can't just throw. He bought into it."
The Dominican Republic native, who remembers hitting triple-digits for the first time before his 18th birthday, has also harnessed his command of the fastball.
"He thought he actually had to work hard to throw 100," Patterson said. "I think he recognized that less is more, rather than if I try to throw 101 I might throw 99, and if I try to throw 90, I throw 101. It's pretty amazing."