In typical Mike Riley fashion, when asked to name his biggest concern heading into spring ball, the dean of the conference coaches countered with a quip: “Do I have to just name one?”

Well, at least he doesn’t have to worry about a quarterback competition this spring. But there are several to-do’s on his checklist. Among them: Rework the offensive line, solidify the defensive line, shore up the secondary and pick a backup quarterback.

Oh, yeah: “Find a way to replace 128 catches,” he said, referring to Biletnikoff Award winner Brandin Cooks, who left school early for the NFL draft.

It’s actually the success of Cooks and quarterback Sean Mannion that led to one of Riley’s biggest pet peeves last season: the inability to successfully, consistently, run the football.

Several times last year, Riley stated that he wanted the Beavers to be more balanced. Then again, when you have a strong-armed quarterback such as Mannion and a phenomenal receiver such as Cooks, the temptation is there to air it out as much as possible.

But with Cooks gone, Riley said he’s looking to make a return to a more balanced rushing attack. In 2011, the Beavers averaged just 86 yards per game on the ground -- last in the conference. Then, in 2012, they brought that number up to a respectable 124 yards per game. But they slipped again in 2013 with just 94 yards per game on the ground.

“I think ... what caused the most problems for us in the season offensively was when we got to the real good defenses,” Riley said. “We played the top three defenses in the league three weeks in a row -- Stanford, Arizona State and USC -- and not running the ball is really a detriment to winning those games. We didn’t. We’ve got to be more balanced.”

The Beavers rushed for more than 100 yards in five of 13 games last season. In six games, they gained 74 yards or fewer, including a season-low 10 against San Diego State and 17 against Stanford. However, the final two games offered a glimpse of what Riley wants his offense to look like. The Beavers rushed for a season-high 231 yards in a Civil War loss to Oregon and 195 yards in the Sheraton Hawai'i Bowl victory over Boise State.

“Those were two good-looking football games offensively,” Riley said. “That is a way better picture of our ideal look. Good balance, good play-action passes. I think it really helps the offensive line. It helps the quarterback. It helps in protection if you can run the ball.”

Storm Woods and Terron Ward are already separated by an “or” on the depth chart and the status of the offensive line further complicates things. The Beavers have to replace three starters on the offensive line: left tackle Michael Philipp, left guard Josh Andrews and right guard Grant Enger. Though standout center Isaac Seumalo returns, he’ll miss spring ball with a foot injury and Josh Mitchell will miss the session with a shoulder injury. Both are expected back for fall camp. Returning tackle Sean Harlow is tentatively slated at left guard, but he’s versatile enough to move around the line and will get some snaps at center.

“You’d love to start developing the chemistry with the starting five as soon as you can,” Riley said. “Because of competition reasons and injuries, we’re not even going to be close to that in spring ball. We just have to develop players and then find out who fits into that top five.”

As for the guy who is handing the ball off, there’s no debate this spring. Mannion is back after a record-setting 2013 season. The battle to be the backup, however, is up for grabs between Brent VanderVeen and Kyle Kempt.

“It is an open competition,” Riley said. “Even though Brent is a year ahead, I think we need to let that thing evolve and let those guys compete to see who is going to be the backup.”