Now, with the 2010 behind him and a promising season ahead in 2011, Persa is determined to put his injury behind him.
"Any time you have a catastrophic injury like that, you're going to think about it right away," he said. "But one you get going and you prove to yourself you can drop and you can reset your feet as quick as you used to, I mean it kind of leaves your head."
Despite his injury, Persa is still considered one of the top quarterbacks in the Big Ten and in the country. He was a first-team All-Big Ten pick by the conference coaches in 2010 despite missing the season's final two games, and in addition to be a top runner and dual-threat quarterback, he led the nation in pass completion percentage last season.
Northwestern has started a Heisman Trophy campaign for Persa, placing promotional billboards in Chicago and Bristol, Conn.—the home of ESPN—and sending 80 media members and Heisman voters a pair of seven-pound purple dumbbells.
Persa is handling the hype well, and while he isn't letting it get to his head, he understands that the situation is unique for Northwestern.
"It's cool; it is what it is," he said. "I didn't come up with it or anything like that. Like I've always said, anything that gets more attention to our program, more people at our games and watching our games, I'm fine with that."
Despite the outstanding numbers and the clutch play last season, some critics doubt Persa's ability to put up the same statistics coming off injury. Coach Pat Fitzgerald isn't worried and is happy with his quarterback's progress.
"He's 100-percent healed. He's going to work on getting stronger and continue to strengthen (his Achilles)," Fitzgerald said. "He's kind of going rehab regiment on top of meetings, on top of practice, so he's got a lot on his plate, but he's handling it really well, so yeah he's right on course. We feel great about where he's at."
Persa feels great about his progress as well.
"Once I got into the team situations I felt really comfortable," he said. "I felt like I picked up where I left off from my reads and stuff like that, and I felt like I was seeing things really well. I'm just looking forward to tomorrow and just keep taking steps."
Fitzgerald had a similar experience to Persa's while he was a player at Northwestern. He was a star linebacker, but was injured in a game against Iowa in 1995, and forced to sit out for the final game of the regular season and for the Rose Bowl.
Fitzgerald has been able to use his experience to mentor his quarterback and give him confidence in his recovery.
"My experience, as a player, I didn't get cleared until about three weeks after Danny got cleared, and it took me all of training camp to get myself in shape," he said.
"I said, ‘How you doing today?' and he said, "Man, like you said I was going to be rusty, I'm rusty, but it's great to be out here.' So his attitude is awesome and I just couldn't be more happy for the young man. He's worked so hard, he's put himself in a position, I think, to have a very special year, and it's just kind of these last hurdles to get over that are the most frustrating."