Colin Kaepernick underwent surgery on his right thumb and left knee.

Kaepernick was in Colorado for a check-up on his surgically repaired left shoulder.

It raises the question of whether Kaepernick will be healthy enough to pass a physical on April 1, when $11.9 million of his contract for the 2016 season becomes fully guaranteed.

"Once again, I'm preparing to be healthy and win the Super Bowl," Kaepernick said in the 49ers' locker room on Monday. "That's all my focus is."

Kaepernick said increased pain and swelling in the right thumb area made him decide to get an MRI last week, which revealed a torn ligament.