"He took it easy for the first half of the session, got a good feel for it," Holaday said afterwards. "And then when he was comfortable, he let 'em rip, and the ball was coming out really good."
He threw some hard fastballs, and a slider or two that resembled the biting 89-mph monster he threw when he was last healthy. He threw a few more hard pitches than he did in previous session last Friday. He'll throw a few more when he pitches again on Thursday.
"He popped a few at the end. That's good," manager Brad Ausmus said. "I think as he gets more and more comfortable, he'll probably start popping a few earlier in the bullpen."
At 11 months out from Tommy John surgery, Rondon is going to receive the cautious treatment. While other Tigers pitchers have been throwing off the mound every other day, Rondon is throwing every third day. He'll be treated similarly once games begin next week.
They're trying to build his arm strength and get him ready for the season. Still, this is where his season ended abruptly last year, diagnosed with a torn ligament after lingering soreness. They tried to ease him back from the elbow issues that ended his 2013 season, and they ended up missing him badly for the second consecutive postseason.
"You're not just building his arm strength," Ausmus said. "You're trying to build his arm strength and avoid a setback from surgery. And I don't know if there's any medical truth behind it, but I think the theory is, heat the elbow up, get it going and let him warm a little more and more. Let him get to the point of almost letting it go, and then finally you can let him go."
The Spring Training progression for most relievers usually ends with pitching on back-to-back days to get the arm used to the in-season workload. That might not happen with Rondon, at least in camp.
"We don't have to do it," Ausmus said. "I guess you could go into the season knowing he hasn't gone back to back and then if you think he's ready at the end of April, go back to back. I guess you could do that. Ideally, we'd like to know if he could do it before we left Lakeland, though."
If they can't, they'll take what they can get out of Rondon in any games.
"A healthy Bruce throwing strikes? I mean, any team could use a guy like that," Holaday said.