Arizona’s struggling offense will get a boost this weekend from the return of its starting quarterback.

Exactly who that starter is, however, remains in question, with UA head coach Mike Stoops saying the decision will be announced prior to tomorrow’s 3 p.m. kickoff, when Arizona (3-5, 1-4 Pacific 10 Conference) travels to Pullman, Wash., to take on No. 25 Washington State (6-3, 4-2).

“”It’s just going to be a game-time thing,”” he said.

The return of quarterbacks Willie Tuitama and Adam Austin from injury has given Stoops options under center against the Cougars – options he lacked when forced to trot third-string Kris Heavner out for most of Arizona’s 17-10 loss to Oregon State two weeks ago.

One thing is certain: Stoops said all three quarterbacks would be available to play on Saturday if needed. He also gave one hint of who’d lead the offense on its first drive.

“”It’s going to be Adam or Willie,”” he said. “”We feel good about both of them. … Both their abilities are very similar.””

The uncertainty at quarterback didn’t seem to faze Cougar coach Bill Doba.

“”No matter who it is, it’s the same offense,”” he said. “”It’s not like (quarterbacks Brady) Leaf and (Dennis) Dixon at Oregon, where one’s really fast and one’s more of a thrower.””

Tuitama, who returned to practice last week after nearly a month away stemming from two concussions earlier this season, has seen the majority of the snaps with the first unit in practice all week.

The sophomore will sport a new helmet designed to prevent concussions, and he said his recent string of head injuries would have no effect on his play.

“”You can’t go out there and play timid, you know, ‘What if this happens? What if that happens?’ because then you’re just going to be off,”” said Tuitama, who’s also been working on avoiding hits in the pocket after practice. “”Basically, just don’t think about it, just go out there and play.””

Heavner, meanwhile, managed the UA offense – which ranks 113th in scoring and 114th in total offense – well against the Beavers, going 17-of-26 for 161 yards, but Stoops said his lack of reps throughout the season limited Arizona’s ability to throw.

With either Tuitama or Austin, who tore a ligament in his left knee against Stanford Oct. 14, calling the snaps, the offense will become much more two-dimensional.

“”It gives us more flexibility in our offense,”” Stoops said. “”Throwing the football gives us more options. (Washington State) is a team that we can’t let stack the box (to focus on the run).

“”We have to be able to throw the ball vertically to get some big plays,”” he added. “”We’ve got to keep trying to find some big plays, and take our chances.””

But should his offense continue to sputter, the third-year head coach realizes that Arizona’s stifling defense “”has to continue to lead the way.””

“”I think you look at every other team, and they have balance,”” Stoops said. “”We don’t have balance in our team right now, and that really keeps you from winning consistently.””

The defense, which would give up a conference-best 17.4 points per game when factoring out the 21 points opponents scored on interception returns, has been the most consistent aspect of the team this season.

“”From what I’ve seen, their defense is really the strength of their team,”” said Cougar quarterback Alex Brink, the reigning Pac-10 Offensive Player of the Week.

But what Stoops termed “”weak quarters”” have cost the Wildcat defense dearly.

In the Washington game, it was a six-minute span in the second quarter that saw the Huskies put up 21 points. Against Oregon State, it was the Beavers’ 14 points over an eight-minute span in the first quarter. Even Division I-AA Stephen F. Austin, which scored all 10 of its points in the second quarter, took advantage.

“”I tell (the defense), ‘If you’re going to be the strength, you’ve got to be the strength every time you step out on the field,'”” Stoops said.

Added cornerback Wilrey Fontenot: “”Every film we go into and watch, it’s always one quarter that we have a letdown. Our biggest goal is to just go out and play a full, complete game.””

This season, Washington State’s enjoying much of the success many thought Arizona would enjoy this season. Already bowl-eligible, the Cougars are ranked for the first time since ending the 2003 season at No. 9.

“”It kind of goes back to the beginning of the year, when people thought we probably weren’t going to be in this situation,”” Brink said. “”Obviously, we feel confident going into this game, and now some other people around the nation are definitely taking notice.””

Arizona’s a team desperately seeking to get into the win column – “”We need to win. With everything right now, we need to win. That’s the key – we need to win,”” said cornerback Antoine Cason – but the Cougars are well aware of that fact.

“”That’s certainly something we have to be guarded against,”” Brink said. “”They’ve played a lot of really good teams, and they’ve played them well.

“”Having them come to our place after a bye week, they’re obviously going to be ready to go and looking for something to turn their season around.””

– Tom Knauer contributed to this report