Monday was a big day for the Seahawks, their first full day of football practice at their shiny new headquarters on the shores of Lake Washington...

RENTON — Monday was a big day for the Seahawks, their first full day of football practice at their shiny new headquarters on the shores of Lake Washington.

Monday was even more important for center Chris Spencer, defensive back Jordan Babineaux and quarterback Matt Hasselbeck. All three key players participated in at least part of practice after missing significant time with injuries.

Spencer suited up for the first time since the first day of training camp, July 25. Expected to be the team’s starting center, Spencer has been kept from doing much of anything because of lower back pain. But a change in treatment led to a breakthrough in his recovery and allowed Spencer to return.

“I had a hard time getting out of my stance,” he said. “I spent all season rehabbing both of my shoulders and my thumb, and then my back started having problems and it was kind of like, ‘Good night.’ Very frustrating.”

Spencer didn’t do team drills, nor did he take part in one-on-one pass rush drills. It’s unclear whether he’ll play in the next exhibition game at San Diego on Monday

Hasselbeck participated in all of practice, including team drills, for the first time since twisting his back after a throw in the Minnesota exhibition Aug. 8.

“I’m fine,” Hasselbeck said. He expects to play at San Diego.

Babineaux also made a full comeback, taking part in drills for the first time since suffering a knee injury during an Aug. 2 scrimmage. Babineaux, who later took part in special-teams practice, is not a starter, but he has been the team’s third cornerback and also plays safety and special teams.

“I felt good just getting my feet back up under me and getting my timing down,” Babineaux said.

He was injured when his foot got caught in the turf at Qwest Field.

Notes

• Coach Mike Holmgren said right tackle Sean Locklear has a sprained ligament in his left knee and that it will require rest, not surgery. The coach still hopes Locklear will be back for the regular-season opener.

• Holmgren after watching film from Saturday’s game: “We played a horribly sloppy game. … It was horrible, and I won’t stand for it. Coaches or players.”

• Defensive coordinator John Marshall said rookie DE Lawrence Jackson will start for the second straight exhibition game on Monday. Jackson and veteran Darryl Tapp are competing for a starting job.

• Backup QB Seneca Wallace was held out of practice with tightness in his groin but will be fine, Holmgren said.

• DE Patrick Kerney took part in all of practice. Kerney has had a calf injury that has kept him out for a good part of camp.

José Miguel Romero: 206-464-2409 or jromero@seattletimes.com