Matt Cain continues to progress in his recovery from elbow surgery, but admitted Tuesday that he is dealing with lingering discomfort.

Cain took another step toward rejoining the San Francisco Giants' season-opening starting rotation by throwing 75 pitches over five innings in a Triple-A exhibition against the Chicago Cubs.

"That was the whole goal, to get out there, get some innings in and get the pitch count [elevated]," Cain said. "My arm strength felt pretty good."

However, Cain acknowledged that he felt "a little bit sore" after some outings and even during them.

The 30-year-old pitcher was warned that he might experience days like this, particularly as he continues to adjust to throwing at full force.

"At first when it happens, you're not really used to it," said Cain, whose next start has yet to be scheduled. "So you have to lean on the trainers a lot and know that these guys have heard this before from guys who have gone through the same situation. You have to trust that those guys know what they're doing. And they have done a good job of trying to calm it down if it does get a little bit sore."