Jim Delany, Mike Slive battle off the field

There are many great rivalries in college football.

Auburn-Alabama. Ohio State-Michigan. USC-Notre Dame.

But the hottest of them all just might be Slive-Delany.

That's right, Southeastern Conference commissioner Mike Slive versus Big Ten conference commissioner Jim Delany. Bowl Championship Series executive director Bill Hancock said that as a whole, conference commissioners are "usually the smartest people in the room." But when the 11 men who run the leagues that make up the Football Bowl Subdivision get together, the guys constantly vying to be the smartest of the smart are Slive and Delany.

They're the straw bosses, men who have come from outside their league's geographic footprints and raised them to new levels of prominence and profitability. Creative Pac-12 leader Larry Scott has made a splash in a hurry, but Delany and Slive have the skins on their walls and the years of service under their belts to remain the most influential men in college sports.

"If you want to get something done," said one college administrator who knows them both well, "you've got to start with Mike and Jim."

Problem is, Mike and Jim don't much care for each other, even though they're careful to say the right things publicly.

Slive on the relationship: "I would characterize it as highly competitive. But it's nice on occasion for us to find some common ground that relates to the long-term health of intercollegiate athletics."

For his part, Delany said he recommended Slive as SEC commissioner to former Arkansas chancellor John White when Roy Kramer stepped down in 2002, and that the two are largely in lockstep on issues related to academics and student-athlete welfare.

"There's a lot of competition on game day and relatively little otherwise," Delany said. "… Mike and I could be in a meeting for a couple hours and not have a disagreement on a lot of major issues."

But many others who have shared space with the two men in meetings and otherwise insist that the rivalry is spirited. The stakes are often big in the commissioner discussions, and so are the egos of the two main characters.

"It is contentious and competitive between them," said the administrator.

Their leagues are not natural rivals. The only long-standing series between member schools has been Indiana versus Kentucky in football (they no longer play) and basketball (they still play annually). That began to change in the early 1990s, when Delany suggested to Kramer that the two leagues match representatives in bowl games such as the Citrus, Outback and Music City.

In recent years the SEC has won a pair of national championships at the Big Ten's expense, with Florida and LSU handily beating Ohio State for the 2006 and '07 crowns. So even though the Big Ten is the oldest conference in the country and in some ways still considered the most prestigious, the SEC has the hardware with five straight national titles.

"This is so much Sun Belt versus Rust Belt, and the best players are in the Sun Belt now," said another college insider who knows both men. "It's made Jim combative, because he knows he can't compete anymore."

There are other areas of conflict, in both style and substance.

Slive is a proponent of a playoff in college football, most likely the plus-one model. Delany is the single biggest roadblock to a playoff, championing the bowl system.

When Delany flexed Big Ten muscle last year with a protracted look at expansion that added Nebraska and threatened to alter the makeup of college athletics nationwide, some in the SEC rolled their eyes. They thought he was milking the moment and enjoying the attention he couldn't get from on-field football success. Slive's recent comment on expansion -- "We could get to 16 teams in 15 minutes" -- could be interpreted as a shot.

Delany, a former NCAA investigator, strongly criticized the NCAA's ruling that allowed Auburn quarterback (and SEC standout) Cameron Newton to stay on the field last season after his dad violated rules. SEC officials fumed privately when Delany involved himself in appealing for Ohio State players retaining their eligibility for the Sugar Bowl (and a matchup with the SEC's Arkansas) after NCAA violations.

Their meeting-room personalities are divergent, as well. Delany is from South Orange, N.J., and has a Jersey bluntness to him. Slive is a Dartmouth grad with a more measured, Ivy League approach.

"Jim can be like a defense attorney cross-examining a witness," said Big East commissioner John Marinatto. "He's got a follow-up question for every answer. He's always engaged in the discussion.

"Mike likes to listen a lot. He takes notes. Then at the end of the discussion, he'll present a summary of the discussion. He's like E.F. Hutton: when he speaks, you listen.

"They're the opener and the closer, in some respects," Marinatto said. "But they both contribute a lot to intercollegiate athletics. They fence, obviously, during our meetings, but there's a competitiveness that makes them very, very good at what they do. They're tremendous stewards of their respective conferences."

Pat Forde is a senior writer for ESPN.com. He can be reached at ESPN4D@aol.com.