That's exactly what touched off a bloody skirmish that left a Texas-shirt-wearing fan nearly castrated and an Oklahoma fan facing aggravated assault charges that could put him in prison for up to five years.

The shocking case has set off a raging debate in this football-crazed region about the extreme passions behind a bitter rivalry. Some legal observers have even questioned whether this case could ever truly have an impartial jury.

"I've actually heard callers on talk radio say that this guy deserved what he got for wearing a Texas T-shirt into a bar in the middle of Sooner country," said Irven Box, an attorney in this city 20 miles from Oklahoma's campus in Norman.

According to police, 32-year-old Texas fan Brian Christopher Thomas walked into Henry Hudson's Pub on June 17 wearing a Longhorns T-shirt and quickly became the focus of football "trash talk" from another regular, 53-year-old Oklahoma fan Allen Michael Beckett.

Thomas told police that when he decided to leave and went to the bar to pay his tab, Beckett grabbed him in the crotch, pulled him to the ground and wouldn't let go, even as bar patrons tried to break it up. When the two men were separated, Thomas looked down and realized the extent of his injuries.

"He was wearing a pair of white shorts, which made it that much worse," Thomas' attorney, Carl Hughes.

It took more than 60 stitches to close the wound, and police interviewed Thomas at a nearby hospital emergency room.

Beckett's attorney, Billy Bock, concedes that his client commented about Thomas' shirt, but said it was just good-natured ribbing and that he apologized to Thomas when it appeared to upset the Texas fan. Later, Bock said Thomas approached his client at the bar and threatened him.

"My client is a little man, and this guy (Thomas) is 30 to 40 pounds bigger than him," Bock said. "He's bigger, stronger, younger and probably faster, and he aggressively leaned in and touched my client and threatened to beat him up. ... My guy was defending himself and just took control of the situation."

Thomas' attorney disputes Beckett's version.

"That's total malarkey," Hughes said. "My client never said a word to him. He got up to pay and when he paid and left a tip, the guy grabbed him."

Beckett, a 53-year-old church deacon, federal auditor and former Army combat veteran, has pleaded not guilty. His next court appearance comes Oct. 4, two days before the Sooners and Horns tangle in their annual football game at the Cotton Bowl in Dallas.

Thomas, who once lived in Houston and became a Texas fan during the heyday of star running back Earl Campbell, is still recovering from his injuries but has returned to work as a meat cutter at a Sam's Club warehouse store.

Like Beckett and Thomas, many fans of the two college squads never attended either university, but have come to identify so closely with these teams that they attach banners to their cars, wear team colors on game day and even have programmed their car horns to play school fight songs.

Dallas police Sgt. Andy Harvey, a 12-year veteran of the force, said it's not uncommon for fights to break out between fans of the two schools.

"People are passionate about their teams and their universities, and that's a good thing," he said, "but when you mix a real passionate sports fan and then get a little alcohol in there, sometimes it's not a good mix."

On both Texas and Oklahoma fan Web sites, boosters trade familiar tales of having their car tires slashed or windshields smashed for sporting the opposing team's sticker in enemy territory.

Assistant District Attorney Scott Rowland said the rivalry will have no bearing on the way the case is prosecuted.