With two high-powered offenses that like to get up and down the floor in a hurry and memories of Arizona’s shootout against Washington last week still fresh, Sunday’s 6. p.m. contest in McKale figures to be much of the same.

But the upperclassmen of No. 10 Arizona (13-2, 4-1 Pacific 10 Conference) say the game depends on defense.

“”All five guys have to play ‘D,'”” McClellan said. “”We can’t have four guys playing defense and one guy not.””

That won’t be easy against an Oregon squad (15-1, 3-1) off to its best start in 69 years and averaging 81.9 points per game before last night’s 60-55 win over ASU, which was good enough for third in the conference.

After last night, Oregon matched its victory total from all of last year (15-18) with 14 games to go before the Pac-10 Tournament.

“”We’ll be challenged on Sunday,”” said UA head coach Lute Olson. “”Oregon will be the quickest team we’ve faced, as well as one of the top 3-point shooting teams.””

After a strong first-half defensive performance against Oregon State yesterday, the Wildcats let the Beavers back into the game by allowing 45 points on 58.1 percent shooting in the second half, 22 of which came in the paint.

“”We keep saying defense is a full-time job, but some of our guys think it’s a part-time job,”” Olson said.

The key to stopping Oregon starts with senior guard Aaron Brooks, who is finally fulfilling much of his potential by leading the conference in scoring entering the weekend at 18.1 points per game. Brooks struggled last year with the off-the-court responsibilities of becoming a father, which Oregon head coach Ernie Kent said impacted him mentally last year before adding he is much more mature this season.

He’s also been helped by the addition of freshman guard Tajuan Porter, a strong shooter who has sometimes struggled with shot selection but has also brought leadership in his first season.

“”He takes the pressure off of Aaron Brooks, who’s having a phenomenal year because of Tajuan Porter being on the floor with him and Aaron not having to handle the ball as much,”” Kent said in a conference call. “”Yet at crucial times in the game we can give Aaron the ball back, and he can run the offense for us.””

Brooks earned Pac-10 Player of the Week honors last week after averaging 28 points and four assists on 64.5 percent shooting, including the game-winner with 13.9 seconds left against then-undefeated and No. 1 UCLA.

The Ducks, who played 12 of their first 15 at home, will play their second game of a stretch in which six of eight are away from Eugene, Ore., where they got their signature win of the season last weekend against UCLA. It was the third time in school history they beat a No. 1 squad.

Guard Malik Hairston returned to the Ducks lineup yesterday after missing five games, scoring 13 points and grabbing eight rebounds against the Sun Devils. Hairston, who last year averaged 17 points per game against the Wildcats, gives Oregon another potent scoring weapon to go with Brooks, guard Bryce Taylor (15.9 points per game) and Porter (13.9).

Oregon forward Maarty Leunen, although thin at 215 pounds, leads the conference in rebounding at 10.3 per game entering the weekend.

But although both teams’ signature is offense, Shakur knows which end of the floor will make the difference.

“”We’re really going to have to pick it up on the defensive end,”” he said.

UA guard Jawann McClellan has struggled thus far in conference play during the second game of the weekend after playing well in the first. Through the first two weeks, he averaged 19 points per game in Thursday games and 4.5 on Saturdays.

UA head coach Lute Olson said he thinks the extra day off for the Sunday game will make a difference for McClellan, who has chronically bad knees.

McClellan looked spry dunking and getting fouled by OSU center Kyle Jeffers in the first half yesterday against the Beavers, although he only scored eight points in the game.

In the locker room after the contest, with ice bags on his knees, he said it’s not an issue.

“”I’m just fine,”” McClellan said. “”I didn’t play well against Washington State. I’m not really worried about it.””