It’s time to make a statement.

The No. 13 Stanford football team will play one of its most hyped games of the season on Saturday, as it welcomes No. 15 Arizona to Stanford Stadium. With identical 4-1 conference records, the Cardinal and the Wildcats are tied for second in the Pac-10. The winner of this weekend’s game will hold on to hopes for a BCS bowl berth, while the loser will see its Rose Bowl aspirations extinguished.

Despite its high national ranking, Stanford (7-1, 4-1 Pac-10) lacks a true “statement” win this season. None of its seven wins has come against an opponent currently ranked in the top 25 of the BCS standings. Meanwhile, Stanford’s only loss came against Oregon, currently the top-ranked team in the country.

The Wildcats (7-1, 4-1) achieved a big win in the third week of the season, taking down then-No. 9 Iowa, 34-27. However, Arizona has not looked as sharp in Pac-10 play. It fell to Oregon State at home, 29-27, in early October, barely edged out a weak California team, 10-9, and struggled last week at UCLA before pulling out a 29-21 win.

Stanford is coming off a big 41-0 win last weekend in Seattle over Washington. The Cardinal looked dominant on both sides of the ball; the offense rolled up yards seemingly at will, while the defense bounced back from a string of poor performances to suffocate Husky quarterback Jake Locker and the Washington running game. Overall, Stanford is third in the Pac-10 in scoring defense, giving up 21.3 points per game.

Stanford redshirt sophomore quarterback Andrew Luck continued his strong play against Washington, going for 192 yards on 19-26 passing and adding five carries for 92 yards on the ground. Luck currently ranks first among Pac-10 quarterbacks in both pass efficiency and total offense, and thanks largely to his efforts, Stanford is fifth nationally in scoring offense.

Last weekend against Washington, Luck made more plays with his legs than usual. The Cardinal called several plays that were designed as runs for Luck, or option runs involving Luck and sophomore running back Stepfan Taylor.

“We’d like to mix in some of those good [plays],” said Stanford head coach Jim Harbaugh.

Of course, the Wildcats have a star quarterback of their own in junior quarterback Nick Foles. While Luck leads a talented crop of Pac-10 quarterbacks, Foles is not far behind, ranking third in the conference in pass efficiency and second in passing yards per game.

While Foles has not played since suffering a knee injury three weeks ago, his backup, junior Matt Scott, has played extremely well in his absence. Scott threw for 319 yards last week against UCLA, and has accumulated over 600 yards of offense in his last two starts. Unlike Foles, who is more of a traditional pocket passer, Scott also has the ability to make plays with his legs–he ran 12 times for 71 yards against the Bruins, and went for 65 yards on seven carries against Washington a week earlier.

Arizona head coach Mike Stoops has indicated that Foles is healthy and ready to start this weekend, but Harbaugh is hedging his bets.

“Both those guys bring some differences, but there are a lot of similarities between the two of them,” Harbaugh said. “We don’t know who’s starting or who’s going to be playing the most in the game. Right now, we’re assuming it’s Foles, but we’ll see.”

While the quarterback matchup is compelling, another significant storyline is the showdown between Arizona’s defense and the Stanford offense. The Wildcats lead the Pac-10 in scoring defense and rushing defense and rank second in pass defense. Nationally, Arizona is seventh in scoring defense.

Arizona’s defensive line is especially impressive, boasting two top-tier defensive ends in seniors Ricky Elmore and Brooks Reed. Elmore leads the Pac-10 in sacks with eight for the season (an average of one per game), while Reed is second in the conference with 5.5 sacks. Freshman defensive tackle Justin Washington has added four sacks.

That line will present the toughest challenge that the Stanford offensive line has seen this season. To date, the unit has lived up to its billing as one of the best in the country. Luck has been sacked only three times all season, and the line has opened up big holes for Taylor and the running game.

However, while the Arizona defense is strong up front, it has some weaknesses in the secondary. The Wildcats’ Sept. 18 game against Iowa revealed their weaknesses in passing defense, as Hawkeye quarterback Ricky Stanzi threw for 278 yards on 18-33 passing and posted three touchdowns against one interception. The Arizona pass defense also came up short in the Wildcats’ only loss of the season to Oregon State. Beaver quarterback Ryan Katz shredded the Cats for 393 yards on 30-42 passing, and the Beavers prevailed despite having star running back Jacquizz Rodgers bottled up for 83 yards on 25 carries.

Meanwhile, the Stanford defense will look to repeat its performance from last weekend, when it shut out Washington on the road. Going into the game, the unit was coming off a series of weak performances, headlined by giving up three fourth-quarter touchdowns to lowly Washington State. However, the Cardinal is eager to prove that its performance against the Huskies was not an aberration.

“This defense is more talented than what we have shown the past couple of weeks, and we made it extra motivation to get back on track and show the Pac-10 that this defense is a force,” said sophomore linebacker Shayne Skov after the Washington game.

The Card will continue to rely on a quartet of talented linebackers–Skov, senior Owen Marecic, redshirt sophomore Chase Thomas and redshirt junior Thomas Keiser–to keep pressure on the Wildcat backfield and force Foles into mistakes.

Stanford will also look for a strong performance from its defensive line, which was instrumental in shutting out Washington last week. Redshirt senior defensive end Brian Bulcke and senior nose tackle Sione Fua kept the Huskies’ offensive line engaged all game, which freed up the linebackers and defensive end Matt Masifilo to make plays. Masifilo finished the game with two sacks and five tackles overall, while Thomas added nine tackles and Skov checked in with eight of his own.

Like Arizona, the Stanford secondary has not played well so far this season. Fifth-year senior cornerback Richard Sherman and his counterpart, junior Johnson Bademosi, have been routinely beat on coverages. However, the unit should benefit from having junior safely Delano Howell at full health.

Stanford will take on Arizona in a high-profile Pac-10 battle on Saturday at Stanford Stadium. Kickoff is scheduled for 5 p.m.