Did USC break an NCAA rule by switching jersey numbers?

Every FBS roster is bound to have a handful of duplicated numbers. No. 12? He's the starting cornerback and the backup quarterback. No. 8? Running back and kicker.

It's not a trick: FBS rosters are more than 100 players deep, and until the NCAA allows triple-digits on the back of jerseys, players will double up and share a number.

The only rule, per the NCAA, is that two players with the same number cannot be on the field at the same time. This rule is put into place to avoid the sort of confusion that reigns when two players with the same number step onto the field in a key situation.

Which No. 8 is the punter and which the running back?

You can sense why there might be some confusion. Take USC, for instance. No. 7 belongs to two players, Matt Barkley and T.J. McDonald. One's a Heisman-worthy quarterback. The other's an all-conference safety. Barkley and McDonald cannot be on the field at the same time.

No. 6 belongs to backup quarterback Cody Kessler and backup kicker Alex Wood. USC can't get both backups on the field at once.

But this isn't about USC doubling up on numbers, which is common. Nor is it about USC switching jersey numbers during the week leading into games, which is also fairly common. (A team just needs to officially report which players are wearing which number.)

It's about USC switching jersey numbers during the game itself, which is in clear violation of the NCAA rulebook.

During Saturday's win over Colorado, USC changed Kessler's jersey to No. 35, the same number as punter Kyle Negrete. Kessler was then used on a two-point conversion in the first half. (The try was successful, with Kessler running it in himself, but called back due to holding.) In the second half, reports the Los Angeles Times, Kessler went back to using No. 6.

The NCAA rulebook says the following about swapping jersey numbers: "Numbers shall not be changed during the game to deceive opponents." A team caught doing so will be assessed a 15-yard penalty and "flagrant offenders shall be disqualified."

So that's the rule. Did USC break it? Feel free to argue over whether Lane Kiffin knowingly alternated jerseys so as to confuse Colorado on the two-point try or whether Kessler's jersey change was mere coincidence.

"We change jerseys all the time with our guys," Kiffin said on Tuesday. "We'll change some more this week. Everything's within college rules."

Well, that depends. As noted, changing jerseys during the week prior to a game is certainly within college rules. Changing jersey numbers on the day of a game is a violation. Changing jerseys during a game in an attempt to deceive the opposition comes close to making a mockery of an NCAA rule.