With the Sept. 2 season opener approaching, the University of Hawaii football team still has two openings on the offensive line.

Left tackle Austin Hansen, right guard Adrian Thomas and right tackle Laupepa Letuli appear to be set as starters.

But offensive line coach Gordy Shaw said Brett Leonard, Brysen "Bulla" Ginlack and Bronson Tiwanak are the central players in the competition at left guard and center.

This training camp, Tiwanak, a senior walk-on from Damien, has gotten the most work as the No. 1 center in place of Matagisila Lefiti, who will miss the first three games while recovering from foot surgery.

Leonard, who has practiced at left guard, played extensively at center yesterday. That allowed Ginlack to compete as the No. 1 left guard.

"The starting five is not all set," Shaw said. "We’re still looking at different combinations in there."

Shaw said there is a chance that Leonard, who redshirted in 2009 after transferring from a junior college, could be the starting center when the Warriors open against Southern California.

"That’s a possibility," said Shaw, noting that in learning the position, Leonard "is pretty close right now."

Shaw said Leonard short-hopped two shotgun snaps during yesterday’s passing drills — errors that are correctable.

"He has to develop the confidence to take the same snap swing every time, like how a golfer has the same swing," Shaw said.

Of playing center, Leonard said, "Mentally is one thing. Technique is a whole different story. The other guys have played center a long time. I’m trying to learn the whole thing in two weeks. Everything comes with reps."

As a guard, Leonard is ahead of Ginlack "by a whisker," Shaw said.

Shaw said Leonard has a better grasp of the offense, and Ginlack, a fifth-year senior who also redshirted last year, is "fundamentally better."

Ginlack also might contribute at right guard. Letuli, a sixth-year senior, did not practice yesterday because of back spasms. Kainoa LaCount, the backup left tackle, practiced in Letuli’s place as the No. 1 right tackle.

If Letuli were injured during a game, Shaw said, LaCount would be the likely replacement at right tackle. If Letuli had a long-term injury and there were time to prepare, Thomas would move from right guard to right tackle, and Ginlack would play right guard.

Ginlack’s guard skills have increased value since the Warriors changed blocking schemes. Last season, the linemen aligned in a stand-up position at the snap, except in obvious short-yardage situations. This year, the guards will be in three-point stances in every situation, with the tackles remaining in two-point stances.

Shaw said he is pleased with the play of the five freshman offensive linemen. He said guard David Lefotu and center Kody Afusia are the freshman blockers with the best chance to play this season.

Shaw said the plan is to try to hold out both freshmen for the first three games — USC at Aloha Stadium, and Army and Colorado on the road — then decide whether they will play or redshirt. If there are a significant amount of injuries to the line, Shaw said, both could be activated.