Updated

The No. 10 Oregon State Beavers will try to continue their astonishing season in a tough non-conference test against the BYU Cougars at LaVell Edwards Stadium this weekend.

Entering this season, little was expected from Oregon State but the Beavers have stunned the college football world rising to No. 10 with wins in each of the first four games, most recently a 19-6 victory over Washington State. The Beavers are now 4-0 for the first time since 2002 and at No. 10, the highest ranked Oregon State squad since the 2001 season when the Beavers were also ranked No. 10. The Beavers have collected wins in a variety of ways with the win against Washington State coming from the defense's ability after the offense carried it to a 38-35 win over Arizona prior to that.

"That is going to be really important moving forward, that everybody picks each other up and that we find that way to win," head coach Mike Riley said.

BYU was also in the national rankings this season jumping to No. 25 after a 2-0 start. The Cougars then suffered a pair of difficult losses by a combined four points. BYU has bounced back with consecutive victories, including a 6-3 win in a defensive slugfest with instate rival Utah State.

This series has been split with each team having five wins against the other. Last season BYU won its second straight game in the series with a 38-28 victory at Reser Stadium.

Oregon State's offense has taken a hit with quarterback Sean Mannion out indefinitely with a left knee injury. Mannion had thrown for 1,358 yards this season and seven touchdowns with a 63.3 completion percentage. Taking his place will be junior Cody Vaz who has not taken a snap this season and has only 17 career passing attempts.

"It's very, very disappointing for (Mannion) because he's invested a ton," head coach Mike Riley said while remaining confident in his backup, "We're going to go win the game with Cody. He's a good quarterback and he's been preparing for this for a long time."

The development is particularly troubling for Oregon State due to the offense's reliance on the pass as the second best passing offense in the Pac-12 (339.5 ypg).

Vaz will still have a pair of solid targets to throw to in Markus Wheaton and Brandin Cooks. Wheaton has team-highs with 36 receptions, 498 yards and four touchdowns. Cooks meanwhile, has been more of a deep threat, averaging 18.7 yards per reception while totaling 486 yards. Each is averaging more than 120 yards receiving per game.

However, more will be needed from the running game which has been led by Storm Woods (74 carries, 357 yards, 2 TDs) this season.

The six points that Oregon State allowed to Washington State was a season low and keeps with the Beavers' trend of limiting teams on the scoreboard. Oregon State is ranked second in the Pac-12 in scoring defense (17.0 ppg) at this point, while also ranked fourth in the nation in rush defense (67.3 ypg). The Beavers have also been stingy on third down with a national best 20.4 percent conversion rate by its opponents.

The strength of the unit is in the secondary led by Rashaad Reynolds, who has team-highs in tackles (27) and pass breakups (seven). Jordan Pyer has four interceptions, three of which he collected against Washington State to earn Pac-12 Defensive Player of the Week honors.

In its first season as an Independent program BYU has been on the bottom half of the country in total offense, averaging 398.3 yards per game which is 73rd among 124 teams at the FBS level. The offensive effort has been well balanced though between the pass (1,256 yards) and the run (1,134 yards).

BYU has used two different quarterbacks this season but may have to go with a third this week. Taysom Hill was lost for the season in the win over Utah State, while starter Riley Nelson could possibly be sidelined with an injury. Nelson had completed 58.7 percent of his passes for 754 yards this season with equal numbers of touchdown passes and interceptions (five). Hill had rushed for a team-high 335 yards and four touchdowns, while also throwing for 425 yards and four scores.

If Nelson can't go senior James Lark, who has only six career pass attempts, will get the start.

At the skill positions the Cougars are stocked with solid running backs Jamaal Williams (309 yards) and Michael Alisa (222). Cody Hoffman (31 receptions, 432 yards) and Kaneakua (20 receptions, 248 yards, 4 TDs) give the team a couple of reliable assets down the field.

The offense has not needed to be overly productive thus far due to BYU's punishing defense. The Cougars are ranked fifth in total defense nationally (229.3 ypg), while doing even better in preventing points (8.8 ppg, third). Like Oregon State, the BYU defense excels in big spots, holding teams to just a 40-percent conversion rate in the red zone and a 27-percent success rate on third downs.

Brand Ogletree is by far the team's best tackles with 49 stops this season, including six for loss. Kyle Van Noy (10.5 TFL, 6.5 sacks) is one of three defenders with at least seven tackles for loss this season with Ezekiel Ansah (8.5) and Spencer Hadley (7.0) being the other two.