"Tyler is our quarterback," offensive coordinator Eric Kiesau said.
Cody Hawkins, who had led the Buffaloes to a surprising 14-3 first-half lead over No. 2 Texas on Saturday night, was replaced by Hansen after throwing two interceptions, the first of which was returned 92 yards for a touchdown that turned the tide in the Longhorns' 38-14 win.
After his deep pass was picked off on the next drive, Cody Hawkins was summoned to the sideline, his starting job yanked after throwing nine interceptions in five games.
"He's got to make that throw," Dan Hawkins said. "You can't turn it over in the red zone like that and you certainly can't give it up for a TD."
Hansen's redshirt was burned at midseason for the second straight year because of poor play by Cody Hawkins, a junior who joined his father in Boulder in 2006.
Only last year, the dueling quarterbacks shared the position over the last half of the season.
Not this time.
"I don't want to get in to this back-and-forth, back-and-forth packages, I want one guy and I want the team to see that," said Kiesau, who replaced Mark Helfrich this season. "And right now, Tyler's our guy."
Fans and alumni began calling for Hansen, a sophomore, during the first half of Colorado's opener when Cody Hawkins fell flat in a home loss to rival Colorado State.
"I feel good, I guess I'm getting kind of used to this happening," said Hansen, who burned his redshirt in the sixth game last year.
Kiesau approached Hansen last week to see if he would consider burning another redshirt.
"I talked to my parents about it, talked to high school coaches about it. It came down to when you have the opportunity to play at a D-I college in this atmosphere, you take it," Hansen said. "It came down to that and I'm happy with it. We need to get this thing rolling."
So, when things started falling apart in Austin on Saturday night, Dan Hawkins took the job away from his son and handed the ball to Hansen.
"He's such a trooper and we're just going to go with him," the coach said. "He's earned it. Paid his dues last year and paid his dues this year. We're going to ride with him. He will start next game."
And the one after that. And the one after that ...
"I don't want to go back-and-forth and be wishy-washy," Kiesau said.
He said the Buffs need to get behind one leader.
"I think some two-quarterback situations work. I think for what we're doing, we're going to give Tyler a chance and see if he can run with it."
That's the other thing: Hansen brings more options to the field than his slow-footed predecessor.
He ran for 261 yards in his five games last season, when he came in against Kansas State and led the Buffaloes to a 14-13 win.
Cody Hawkins said he understood the switch.
He called the 92-yard interception return by Earl Thomas "just a terrible pass," and agreed the Buffs had to do something else to try to spark their stagnant offense Saturday night.
The Buffs insisted that there was a quarterback competition throughout camp this season but in reality it was decided early on that Hawkins would be the starter and Hansen would redshirt, although they kept the pick a secret until the opener.
The choice of Hawkins was lambasted by fans and alumni alike when the Buffalos lost at home to their in-state rivals and Dan Hawkins acknowledged he never considered benching his ineffective quarterback at halftime.
Five days later, the Buffs were blown out at Toledo. After beating Wyoming, they lost at West Virginia and then Texas, meaning they would have to win the rest of their games plus a Big 12 championship and a bowl to reach their stated goal of 10 wins.
Hansen said he has no regrets about giving up his redshirt and doesn't look back and wonder what might have been had he won the job in August.
"It's always a little frustrating. You can say, 'Well, maybe if I would have played those first couple of games, maybe we would have won some.' Cody had a good camp and performed well, they made a good decision. Their plan to redshirt me was the right decision at that time," Hansen suggested.
He'll get his first start next week at home against No. 17 Kansas.