"I made a mental mistake; I've just got to learn from it," Allen said Monday. "When I first got to Tennessee, it was kind of like the same thing. I got there and guys were like, ‘Where'd they get this guy? Is he on scholarship?' Because everything was all new for me. I didn't know what to do until I caught on to the system."
It was bad enough that Allen got beat so badly on the play, but then television cameras caught Nick Saban giving him an earful as he returned to the sideline.
Saban later went to talk to Allen on the bench.
"He's doing his job," Allen said. "I don't think I was doing my job to the best of my ability. There weren't hard feelings. It's nothing personal. Coach Saban was doing his job, and I appreciate him for that.
"He was upset because it has nothing to do with ability. I don't know who the guy was, the receiver, but the ability thing is there. My eyes were in the backfield on a play-action pass, and I bit on the run, and that's not my responsibility. I have to get in the mind-set where there are 10 other guys on the field. If you're going to make plays, let plays happen by being in the right place at the right time, not trying to force things."
Of course, in Allen's defense, he's in a tough spot right now after having missed the start of camp and then moving from safety to cornerback last week before playing at that position during the game.
Allen said shortly after being drafted that he prides himself on being able to play everywhere in the secondary, and he's now changing his tune now.
"I'm the type of player, I like to know what's going on all over the field," he said. "I want to get to where I'm playing cornerback maybe one game, the next game maybe playing safety. I think I have that type of ability and the coaches see that in me.
"I just want to play football. I don't have a preference. If I play 20 snaps at corner and 20 or 30 at safety, I'll be happy. Whatever the team needs me to play to help the team win."
If there was one consolation for Allen after Saturday's mistake, it was that it happened during the preseason.
"I'm glad it happened early in my career so I can look back at this two or three years and look back and say, Man, I can remember when I was a rookie and this happened to me," Allen said. "It's just a learning experience. It's all my fault."