Former Oklahoma quarterback Charles Thompson never imagined he'd even consider putting up the "Hook `em Horns" hand gesture.
He's done it now, and for good reason. His son, Casey, will start at quarterback for No. 21 Texas (4-1, 2-0 Big 12) against No. 6 Oklahoma (5-0, 2-0) in the annual rivalry game.
It's a strange situation for the elder Thompson, who lives in Moore, Oklahoma -- a short drive from Oklahoma's campus. Charles ran the wishbone offense for coach Barry Switzer, playing a significant role in Sooner victories over Texas in 1987 and 1988.
"I've been an OU fan since I was six," Charles, a native of Lawton, Oklahoma, said. "Every year, this time of year, I've always rooted against Texas. Even the last few years with Casey on the team, I still kind of quietly wanted Oklahoma to win -- kind of a win/win situation for me. This will be the first year that honestly, I'm really rooting for Texas."
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Charles said he catches some grief from his old teammates with his son playing for Oklahoma's biggest rival.
"I mean, there's surely some joking, kind of messing around a little bit, but I think all of them are kind of in support of him," he said. "They certainly want Casey to have a great game, but want Oklahoma to win.
"I get a mulligan. I want Casey to win."
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Charles won't go so far as to wear Texas' burnt orange, and he said if you gut him open, he'll bleed Oklahoma crimson. He'll wear a custom-made black Texas shirt when he sits with the other parents.
"Well, I've never put on burnt orange," he said defiantly.
The situation has provided an opportunity for Charles to learn a few things about the rivalry from the Texas side.
"All my life, I've always called it the OU-Texas game," he said. "Ask anybody from Oklahoma, they'll say OU-Texas. I got sort of harassed a little bit in Austin because they say Texas-OU. They want Texas first."
Casey is in an odd situation, too. He wore Oklahoma's crimson and cream until his high school days. Another of Charles' sons, Kendal, played for the Sooners, further strengthening the bond between the family and the school.
Casey played high school football at Southmoore High School in Moore before playing his senior season at Newcastle High School in Newcastle, Oklahoma.
As he became a major prospect, his loyalty to Oklahoma waned. Former Texas coach Tom Herman recruited Thompson back when Herman was the head coach at Houston, and Tim Beck had recruited him when he was an assistant at Ohio State. When Herman took over at Texas and Beck became the offensive coordinator and quarterbacks coach at Texas, it made sense for Casey to take a look. He attended the 2017 Red River rivalry game as Longhorns prospect.
Naturally, the locals objected when Texas entered the picture.
"I remember even in high school when I was getting recruited, some of my teachers and best friends were like, `If you go to that school, I'll never root for you, never cheer for you,"' Casey said. "But I'm really not worried about people who are hating. I'm trying to focus on this team and the people who care about me and love and support me."
Though he was highly recruited, his journey hasn't been easy. Even after he stepped in for the injured Sam Ehlinger and threw four touchdown passes in the 55-23 Alamo Bowl win over Colorado, he didn't secure the starting job. Freshman Hudson Card won the spot in the summer and started the first two games.
Casey has taken over and completed 71% of his passes. He has thrown nine touchdown passes and just three interceptions. Now, he has the Cotton Bowl stage.
"It's a dream come true for me to start in this game," he said. "But I don't really think that I'll be nervous or anxious or uptight. I'm excited to play."
Oklahoma coach Lincoln Riley has followed Casey throughout the years and has a good relationship with the family. He's glad to see Casey succeed.
"Here from game three on he has played at a high level, has done some really good things -- moving around, throwing the ball well like he does," Riley said. "I don't wish him success on Saturday. We're going to get out there and compete against each other. But I'm happy for him. I'm glad he's having success. And I'm not surprised."