Carlos Rodon played catch in front of Don Cooper on Monday afternoon but only added to the intrigue surrounding his health when he declined to talk to the media.

On the 10-day disabled list with a biceps strain, the White Sox said Rodon continues to make progress in his rehab program. Cooper said the third-year pitcher felt and looked fine as he played catch in left field. But neither he nor manager Rick Renteria offered many more details on when Rodon may return or even when he could throw off a mound.

"He looked like he played catch good," Cooper said. "His throwing program is progressing. He felt fine. He threw the ball fine. That's kind of where we are at. He threw fine and move on to the next."

Rodon is in town for several days to be observed by the White Sox. On Friday, general manager Rick Hahn described the visit as a "routine follow-up visit." But other than making sure they're cautious with Rodon, the club hasn't been able to offer a specific timetable for their prized pitcher.

"I can't tell you in detail what the program is," Renteria said. "I know it involves throwing and making sure he's getting treatments and making sure it's taken care of, the issue he had with his biceps. We know it's getting better."

But the improvement hasn't made the situation any easier to deal with. When they started him on a delayed program this spring, the White Sox had Rodon pegged for 33 starts and 200 innings. As of now, there's no certainty when he'll make his first turn and the calendar is nearing May.

"He's frustrated," Cooper said. "He wants to get through this, through all of it. We are just there to try to make sure he's doing things right and there's progression.

"Well, I mean we've already taken a lot of caution. He's important to us now and in the future. We wouldn't rush with him or anybody."