Case Keenum was more to the Houston Cougars than just the guy responsible for major edits to the school and NCAA record books.

Keenum had evolved into a Cougars coach on the field, with almost total autonomy to change plays at the line of scrimmage. He made the nation's highest-scoring offense go with his arm, his legs, his head, his leadership.

The Cougars are searching for more than a leader after a lost weekend in Pasadena, Calif. UH lost its standing as a Top 25 team, lost its starting quarterback and backup Saturday night during 31-13 loss to the UCLA Bruins.

Head coach Kevin Sumlin said Sunday night that Keenum (torn anterior cruciate ligament in the right knee) and backup Cotton Turner (fractured clavicle) will miss the rest of the season with injuries suffered one quarter apart against UCLA. Just like that, the Cougars have gone from No. 23 in the nation to a team that will have to forge a new identity. Sumlin said two players he had planned to red-shirt this season, true freshmen Terrance Broadway and David Piland, will move to the top of the pecking order.

'Unfortunate situation'

"It's a blow to our team, really, to lose both of them," Sumlin said. "I'm really disappointed for them personally — particularly for Case. It's one of those things where you don't want it to happen to anybody. It's an unfortunate situation. We've got to have some guys step up and play."

Broadway, who starred at Capitol High in Baton Rouge, La., stepped in late in the third quarter and completed five of eight passes for 84 yards, leading the Cougars to 10 of their 13 points. Piland, who came out of the Southlake Carroll program that has produced the likes of Chase Daniel (Missouri) and Greg McElroy (Alabama), wasn't on the traveling squad for the UCLA game. Sumlin said he will announce early this week the starter for Saturday's Conference USA game against Tulane at Robertson Stadium.

"Based on Terrance's performance Saturday night, obviously that bodes well for him," Sumlin said. "We've got to get a plan in place as coaches to give our young guys a chance at quarterback. And our team, we've been through adversity of all kinds. I don't know if we've been through this kind yet."

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Keenum, a fifth-year senior from Abilene who is fifth on the NCAA career passing yardage list (13,586), blew out his knee trying to tackle UCLA linebacker Akeem Ayers after a second-quarter interception. Turner, a fourth-year junior from Dulles High, suffered his injury when he got hit attempting a third-quarter pass and underwent surgery on Sunday afternoon. Keenum will have the knee evaluated again today.

"Certainly, we're going to have to depend on some leadership from within," Sumlin said. "As I told the team after the game, we've got some experienced players who are going to have to pick up the slack. And that's not necessarily at the quarterback position. But we do have people who will surround our quarterbacks, and they've got to raise their level of play."

Sumlin considered Broadway one of the few bright spots in a game in which the Cougars produced their lowest point total since 2007. Broadway showed his agility during his first drive, which took 13 plays and covered 74 yards.

He teamed up with James Cleveland on a 10-yard pass with 11:39 remaining to save the Cougars from going without a touchdown in a game for the first time since a 50-3 defeat at No. 5 Michigan in 2003.

Newcomer confident

"In light of the reps that he got last week, which were basically none besides warming up and knowing the game plan, he came out and did a good job with a limited script," Sumlin said. "You can't argue with him moving the team for 10 points. In light of everything, I thought he operated very well.

"He's got a lot of confidence, as does David. They prepare mentally, and they're talented, talented guys. The way Terrance went into the game and operated, got on the edge, made plays with his legs and threw the ball effectively, he might bring another dimension to our offense."

The immediate challenge at hand is to make the offense evolve rather than devolve without a coach on the field. The thinning of the ranks came in such rapid fire, the UH offensive staff had only just begun on Sunday to start hatching a plan.

"We can't really have a drastic departure from what we do," Sumlin said. ""We've got some talented young players in (Broadway) and David Piland. Our team is going to have to rally behind our young quarterbacks and continue to move on."

Possible NCAA appeal

One option for UH ­- one that can't pay any dividends this season - is for Keenum to appeal for a sixth year of eligibility. According to the waiver criteria laid out in 14.2.1.5.1 of the NCAA Division I Manual, an appeal could be a long-shot winner.

A waiver of the five-year period of eligibility is designed to provide a student-athlete with the opportunity to participate in four seasons of intercollegiate competition within a five-year period.

This waiver may be granted, based upon objective evidence, for reasons that are beyond the control of the student-athlete or the institution that deprive the student-athlete of the opportunity to participate for more than one season in his/her sport within the five-year period.

The NCAA considers taking a red-shirt year, which Keenum did in 2006, to be an instance that is within an athlete's control.

"We really haven't had a chance to discuss any of those options at this point," Sumlin said.

Instead, Sumlin and his staff are trying to save a season that went from promising to precarious so abruptly.

"We've got a long season ahead of us," Sumlin said. "All of our goals are still out in front of us. Every year, our goals start with our conference. We've got to turn our attention now to still reaching our goals, and our players know that. I think they're in tune to that right now."

steve.campbell@chron.com