So when the Crimson Tide stomped Tennessee in Knoxville during Harper's freshman season three years ago, the free safety didn't get too excited.
Just another game, right?
Flash forward a year – to the aftermath of Tennessee's stunning 51-43 five-overtime victory in Bryant-Denny Stadium.
Let's just say Harper realized what the Alabama-UT rivalry meant – and then some.
"You don't know how big this game is until you actually lose it," he said. "Once you lose one, that's when you start to realize how big this rivalry is and how much it means to so many people. You look at it with a totally different aspect."
Although the Tide has suffered many painful losses during Harper's tenure, the five-overtime defeat was one of the worst. In the third overtime, Alabama was up seven points on the Vols and had them in a fourth-and-19 situation. Stop them, and the game was over.
Instead, Vol quarterback Casey Clausen converted against the Tide secondary, and UT eventually won the game.
Harper said the sick feeling really sunk in after the game was over.
"We still thought we were going to win the game," he said. "I didn't have that feeling until the (the (last chance) ran out. I thought, ‘Golly, we really let this one slip through our hands.'"
"They made a great call, you've got to give it to them. But for us to lose that game that way was heartbreaking, after so many overtimes, so hard-fought on both sides. It put the rivalry into perspective."
This week, Alabama is in perfect position to snap the Vols' two-game winning streak. The Tide is 6-0 for the first time since 1996, and ranked fifth in both major polls as well as the BCS standings. Tennessee, meanwhile, is struggling; the Vols are 3-2 and coming off a bye week after a 27-14 loss to Georgia.
Harper knows this is the perfect time for a victory – not that Alabama fans will be satisfied with anything less.
"Hopefully we come out this week and play hard and come out with a win. We need one big-time, to keep this thing rolling, keep a positive attitude and keep the fans off us," he said. "We go this far and lose now, they'll be pretty upset, so we've got to keep those people happy."
The biggest key to happiness come 7 p.m. Saturday night?
Stuffing the Vols' two-headed quarterback monster. Senior Rick Clausen went the whole way the past two games (a victory over Ole Miss and the Georgia loss), but sophomore Erik Ainge could still play a huge role.
The only real way to prepare, Harper says, is preparing for both.
"Ainge was struggling at the beginning of the year, and Clausen led them to that big win at LSU," he said. "Clausen is playing more now, and both are talented guys. Ainge led them to a great year last year and Clausen is doing the same this year. You've got to understand that and respect both of them."