UCLA’s pass defense is being stretched to the limit this season

On the off chance the telephone rings at Dietrich Riley’s apartment on NFL draft day this spring, the UCLA safety has an answer ready: Andrew Luck.

Stanford’s Heisman Trophy contender would certainly be the first quarterback Riley would pick . . . unless it was Arizona’s Nick Foles.

“Yeah, Foles is just as good,” Riley said.

UCLA defensive players should be a great source for information on quarterbacks heading into the 2012 draft.

The Bruins this season face three quarterbacks currently projected as first-round picks — Luck, Foles and USC’s Matt Barkley. As a bonus, UCLA opened the season against Houston’s Case Keenum, who has risen in draft projections from seventh round to fourth round in two months.

Foles and Keenum are seniors. Luck is a redshirt junior. Barkley is a junior who is eligible to declare for the draft after the season. Add to that group Arizona State junior Brock Osweiler and UCLA will face five quarterbacks currently ranked among the top 20 nationally in yards passing.

“I probably could give some real insight to the NFL,” UCLA Coach Rick Neuheisel said. “We will have been through a real murderer’s row of quarterbacks.”

As for his killer pick, Neuheisel said, “I don’t want to do that. Maybe when I’ve been through them all. I don’t want to tick off people before we play them.”

The Bruins already have been beaten by Keenum and Luck. Foles gets a crack at them Thursday night in Tucson.

Foles’ average of 375.83 passing yards per game is second nationally to Keenum’s 384.83.

“He’s like a point guard. He gets the ball in guys’ hands, puts it where they can make plays,” Neuheisel said of Foles. “We have to understand that we’re not going to necessarily stop him. We just have to contain him.”

Arizona is 1-5 this season, so the Wildcats have been contained, Foles notwithstanding. Of course, Oklahoma State, Stanford and Oregon, ranked fourth, eighth and 10th when Arizona played them, delivered three of the losses.

UCLA is 76th nationally in pass defense and barely survived Washington State quarterback Marshall Lobbestael in a 28-25 victory Oct. 9.

“Foles throws that deep pass down the sidelines,” Riley said. “Usually quarterbacks don’t like to squeeze that ball in there, but I’ve seen him make that play a lot.”

So far, like Riley, UCLA linebacker Patrick Larimore puts Stanford’s Luck at the top of his list. “He came up to the line and knew exactly what he was going to do against us,” Larimore said.

Luck completed 23 of 27 passes for 227 yards and three touchdowns in Stanford’s 45-19 victory over UCLA.

Larimore’s second choice?

“Keenum,” he said. “I came out of that game with a lot of respect for him. We couldn’t get any pressure on him because he got rid of the ball so fast.”

Keenum suffered a season-ending knee injury against UCLA in 2010. He exacted some payback by completing 30 of 40 passes for 310 yards and two touchdowns in a 38-34 victory on Sept. 3.

“Case will have a little bit of an issue [as an NFL prospect] because people think of him as a ‘system quarterback.’” Neuheisel said. “But having been on the sidelines, watching the ball come out his hands and his effortless ability to put it up with touch, he’s pretty special.”

That can be said of about half the quarterbacks UCLA faces, including Osweiler, a 6-foot-8, 240-pound former basketball player who has improved his NFL possibilities.

Last year, Foles was injured when Arizona faced UCLA, and Keenum didn’t make it out of the first half. Luck and Barkley had low-level games, mainly because the Bruins defense gave up rushing yards in large chunks.

But Osweiler had a coming-out party against UCLA, throwing for 380 yards and four touchdowns in a 55-34 Arizona State victory. He gets another shot at the Bruins early next month.

So add him to a list that makes Neuheisel shake his head.

“They are all pretty talented guys,” Neuheisel said. “I would say we have the opportunity to play at least four first-round picks by season’s end.”

chris.foster@latimes.com

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