His decision may come as a surprise, but Mosley said he and his parents knew he was coming back before this season even started. He didn't even reach out to the NFL to check his potential draft status.
"My main thing was just finishing my degree, finishing school," he said. "I just felt like I haven't accomplished everything that I could as far as playing football, and I just wanted to make sure that when I leave school, I don't have any regrets."
Mosley is expected to graduate with a degree in human environmental sciences next December.
Though projected as a first-round draft pick on some boards, one of the biggest holes in his resume is that Alabama hasn't used him as an every-down linebacker. He hopes that in coming back for another year, that will change.
"Most definitely," he said.
Mosley, who was a finalist for the Butkus Award and a consensus All-American, was also voted by his teammates as the Crimson Tide's MVP this season. He said when it was announced at the end of the year awards banquet a couple weeks ago, he was caught off guard.
"I was surprised," he said. "I didn't know I was getting it. I was in the middle of eating some cake when I heard it, so I had to eat it up real quick to get out there. They asked me to say something, but I was shocked and didn't want to go up there and start mumbling."
Though Mosley may not have seen the honor coming, it only seems like the natural selection as he led the team with 99 tackles (no one else had over 56), seven tackles for loss (minus-46 yards), four sacks (minus-34 yards) and two interceptions (one for a touchdown against Michigan) among other impressive stats.
But Mosley isn't just an MVP on the field, but off it, too. Alabama head coach Nick Saban said that Mosley is an example of the type of guy—personally, academically and athletically—he enjoys coaching.
"C.J. is a really good person," Saban said. "I know that he has never been in my office for ever not doing what he's supposed to do, like missing class, or getting in trouble in the dorm, or not doing something he was responsible for, or being late. I mean not once. Not ever once.
"He's very quiet. You don't even know he's around until the ball's snapped, then he shows up big and does what he's supposed to do.
"He's very conscientious, and he's done really well in school here. We look forward to seeing him graduate in the very near future. He's got a wonderful family. This guy is one that will make you proud."
Mosley, who stands at 6-2, 235, said he probably won't play over 240 pounds, but his size doesn't affect his game.
Heading into its third national championship game in four years, Alabama's defense leads the nation in total defense (246.0 yards per game) and rushing defense (79.77), and is second (behind Notre Dame) in scoring defense (10.7 points per game).
With Mosley returning next year, alongside young guns like Trey DePriest, Adrian Hubbard, Xzavier Dickson, Reggie Ragland and Denzel Devall, the Tide has a chance to churn out yet another elite unit. And Mosley will be the leader.
"He's one of the most amazing players that I've played with at the University of Alabama," Square said. "He's great at everything he does. He can pass rush. He can play the run. He can play the pass. There's nothing that coach has ever asked of this guy that he cannot do. He's what a football player is. If you want to be a great football player then I suggest you mock C.J. Mosley."
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