So this is why players never win the Heisman Trophy two times during their college football careers.

One year after Oklahoma quarterback Sam Bradford, the 2008 Heisman Trophy winner, missed nearly all of the '09 season with a shoulder injury, reigning Heisman Trophy winner Mark Ingram of Alabama has gone down with a knee injury.

Ingram, who became the first Alabama player to win the Heisman Trophy, was injured late in Monday's practice and then underwent arthroscopic knee surgery on Tuesday morning. While Alabama coach Nick Saban said Ingram will fully recover and that the injury will not affect his long-term future, the setback puts a serious dent in Ingram's chances of becoming only the second player to ever win a pair of stiff-armed trophies.

Former Ohio State running back Archie Griffin is the only player to win college football's most coveted individual award twice, claiming it as a junior in 1974 and as a senior in '75.

If Ingram misses more than the Crimson Tide's first game -- he already has been ruled out of Saturday's opener against San Jose State at Bryant-Denny Stadium -- there's a good chance he won't join Griffin as the only two-time Heisman Trophy winners.

If Ingram is not ready to go against Penn State at home on Sept. 11, there's a good chance he probably won't be back until the Tide's fourth game, at Arkansas on Sept. 25. If Ingram doesn't play against the Nittany Lions, there's little reason for him to play at Duke in Alabama’s third game. After all, the Crimson Tide, the defending BCS national champions, are going to Durham, N.C., on Sept. 18 to play Duke's football team, not its basketball team.

The news of Ingram's injury broke less than an hour after ESPN.com posted its first Heisman Watch of the 2010 season. Ingram received nine of 15 first-place votes and no other player received more than one first-place vote. Ingram, who ran for 1,658 yards with 17 touchdowns last season, was a runaway leader with 63 total points. Boise State quarterback Kellen Moore was second with 37 points.

Ingram was first on my ballot. He won't be first on my ballot next week, but I'm betting there's a good chance another Alabama running back will be somewhere on my ballot.

If Crimson Tide sophomore Trent Richardson played for any other school in the country, and wasn't playing behind Ingram, he'd already be a Heisman Trophy candidate.