RENTON, Wash. (AP) - Pro Bowl quarterback Matt Hasselbeck fully participated in a practice for the first time since his back stiffened 10 days ago and said he will play in the Seahawks' next preseason game Aug. 25 at San Diego.

"It is fine," Hasselbeck said Monday, two days after he watched No. 3 quarterback Charlie Frye play all of Seattle's preseason win over Chicago. "If I felt stiff, it's because I was standing around too much the last couple days."

Hasselbeck occasionally stretched and rubbed his back in between plays during practice, on the team's first full day at its new $60 million lakeside facility.

When asked if he would play against the Chargers in the third preseason game that is usually the longest starters play before the regular season, Hasselbeck said, "Absolutely, (though) I don't know how much."

Coach Mike Holmgren said Hasselbeck gave him "the thumbs up" Monday that he was back to full health.

"He's feeling pretty good ... he'll play," Holmgren said.

The coach also announced starting right tackle Sean Locklear is out at least two weeks and could miss the Seahawks' opener because of a sprained knee.

"We're hopeful for the first game, but it's going to be close," Holmgren said of the opener Sept. 7 at Buffalo. "It's not an ACL. It's not an operation. It's just rest."

Locklear is wearing a bulky knee brace over a sprained ligament in his left knee. The three-year starter got hurt early in Saturday's game.

Starting center Chris Spencer practiced for the first time this preseason but was held out of team drills while he returns from a lower back injury. He is on track to start the opener, meaning 2007 practice squad player Steve Vallos can go back to being a reserve guard.

Pro Bowl defensive end Patrick Kerney participated in a full practice for the second time. He is returning from a strained calf and offseason shoulder surgery.