Today in Thompson-Boling Arena, they'll be pacing their own turf, roughly 30 feet apart. They'll barely acknowledge each other's presence.
Bottom line, with a nation of college basketball fans watching, they'll be trying to beat each other's brains out.
But you should have seen Bruce Pearl and Billy Donovan 18 hours before tip-off.
There they were on the 11th floor of the Marriott. Outside, Knoxville was a frigid winter tableau. Inside, it was all warm fellowship, the head Vol and the head Gator arm in arm, laughing, chatting, posing for pictures.
The only thing missing was a crackling fire. And maybe Dick Vitale gushing.
Tennessee fans, you might boo Donovan lustily today. He does, after all, represent the University of Florida.
But understand that Saturday night he was a good guy. He accepted Pearl's invitation to drop in at an OUTLIVE cancer fund-raiser, the program that arose from Chris Lofton's bout with testicular cancer two years ago.
Donovan could not have been more gracious, posing for pictures with Pearl and virtually every UT booster in the room. Pearl said the event raised close to $60,000 that will fund cancer-screening tests.
"We're all blessed in so many ways,'' Donovan said. "To me it really doesn't make a difference if you're a Gator, a Volunteer, a Bulldog or whatever it may be.
"In some form or fashion, all of us have been affected by cancer and this is a great way we can all come together and keep the fight.''
Let's frame this picture: the head coach at the University of Tennessee and the head coach of the University of Florida, the night before a crucial game - is there any other kind when these schools meet? - grinning like two old frat brothers.
Would Urban Meyer and Lane Kiffin have developed such bonhomie if given more time? Ha-ha.
I don't know that I can conjure up Phillip Fulmer and Steve Spurrier, arm in arm, all smiles, posing for Gator fans or Vol fans the night before kickoff.
Before Pearl took the UT job nearly five years ago, he and Donovan barely knew each other if at all.
"I think over the course of him being (at UT), there's been a friendship develop,'' Donovan said, "and a bond created.
"It's not like we're talking all the time but if I didn't have respect for Bruce and for Tennessee's program, I wouldn't be coming here tonight. I would have said, 'Bruce, no thanks.' ''
While Pearl was rebuilding Tennessee's program in supercharged fashion, Donovan was harvesting the fruits of his own prior rebuilding efforts in Gainesville. His Gators won back-to-back NCAA tournament championships in 2006 and 2007.
Two of his key cogs were Tennesseans. One, Corey Brewer, the Vols wanted and couldn't get. The other, Maryville's Lee Humphrey, the Vols took a pass on.
But there has been consolation for Tennessee fans: Pearl is 7-1 against Donovan's Gators.
"I believe,'' said Donovan, "competition makes you better. He's made our teams better and he's made me a better coach.''
Today's game won't register as high on the national radar as 2006, 2007, or 2008, when either the Gators or the Vols were ranked in the top 10. It will, however, be just as fiercely contested.
The SEC season is young, but the Vols and Gators are already chasing Kentucky and Vanderbilt in the East standings. Today's loser will fall even farther in arrears - especially if it's Tennessee absorbing another home loss.
There will be a winner and a loser. That's why there is a scoreboard.
But keep this in mind, no matter how that scoreboard reads at the end:
The night before, when both coaches could have bunkered in their respective trenches, they took the time to lay down their swords and get together in behalf of a good cause.
Maybe one of those cancer screenings they raised money for will save a life. And it doesn't matter if that life is a Vol fan or a Gator fan.
Mike Strange may be reached at email@example.com or 865-342-6276.