INDIANAPOLIS — Much like the quarterback position in the 2013 NFL draft, the running backs are a subject of great debate.

As in, who is the best?

Some like the power of Alabama’s Eddie Lacy. Others like the vision and production of Wisconsin’s Montee Ball. Clemson’s Andre Ellington might be among the fastest backs. Stanford’s Stepfan Taylor might be the most polished all-around.

But there is no more intriguing prospect for a host of reasons than South Carolina’s Marcus Lattimore.

Lattimore comes to the Combine with one primary goal that trumps all others: Prove to NFL teams that he is well on his way back from what was a gruesome knee injury that ended his season.

Fans of college football no doubt saw the hit in the Tennessee game that caused his torn ACL, LCL and PCL, and Lattimore made the tough decision to forgo his senior season to enter this year’s draft. Inspired by Broncos RB Willis McGahee, who suffered a similar injury in his final college game at Miami, and emboldened by the remarkable comeback of Vikings RB Adrian Peterson, who overcame ACL and PCL injuries to make a run at the NFL’s all-time rushing mark, Lattimore has similar aspirations. He wants to shock the football world with how fast he heals.

“This is not Marcus Lattimore,” said the NFL’s Gil Brandt, as he introduced Lattimore to the Combine lectern. “This is medical history.”

Lattimore admitted he thought a lot about what might have been.

"Yeah, I used to. The day after it happened, of course,” he said. “I was thinking about what could have been, what could have happened, but I don't think about that anymore. It happened for a reason. The reason for me to come back inspired a lot of people."

For four hours on Friday, NFL team officials and doctors from all 32 teams inspected the knee and gauged his progress. Some liked what they saw. Other teams encouraged him to keep working hard to rehab. Lattimore knows it’s part of the drill.