A year after the 49ers took him in the fourth round of the NFL draft, running back Marcus Lattimore says he’s healthy enough in recovery from the gruesome knee injury that ended his college career that he could take the field today.

Lattimore said his next steps aren’t about rehabbing his knee, they’re just about convincing 49ers head coach Jim Harbaugh that he deserves significant playing time.

“If he wants to put me in, he’ll put me in,” Lattimore told GoGamecocks.com. “If I prove it in practice, I don’t think there’s no excuse why I can’t play. I’m ready.”

The knee injury Lattimore suffered in 2012 was so serious that sitting out his rookie season, as he did last year, was far from his biggest concern. When he first got hurt, Lattimore feared he’d never play football again.

“After my injury, I just wanted to walk again,” Lattimore said. “It was tough, very tough. We’re a playoff team, so we play 20-plus games. Being on that sideline, we got so close to the Super Bowl title the last three years. But I’m blessed to be in this situation. Never would have thought in a million years I’d be in this situation.”

Lattimore has heard the reports that backup running back LaMichael James is not in the 49ers’ long-term plans, which means Lattimore would move up to third on the depth chart behind Frank Gore and Kendall Hunter.

“If that happens, it does put me in that No. 3 spot,” Lattimore said. “But I’ve just got to go in there and work hard. I can pass-protect and run the ball. I’ve got to show that.”

If he can run now the way he ran at South Carolina, Lattimore will show a lot in San Francisco this year.