Lofa Tatupu out for the season with torn pectoral muscle

There's never been any questions about the heart of middle linebacker Lofa Tatupu.

It's his chest that's going to keep him from playing.

Tatupu suffered a torn left pectoral muscle in the second quarter of Sunday's game. The injury will require surgery that will cause Tatupu to miss the rest of the year.

"It's a blow to our team," coach Jim Mora said, "and it's a blow to him as a man."

Tatupu suffered the injury as he tackled Cardinals receiver Larry Fitzgerald in the second quarter. Seattle's trainers examined him on the bench and took him to the locker room with about 2 minutes left in the half.

Tatupu spoke to his teammates at halftime, but had taken his shoulder pads off.

"It was a little confusing," quarterback Matt Hasselbeck said. "He's not in uniform, he's wrapped up and he was making it sound like he wasn't going to be out there the rest of the day."

Guard Rob Sims suffered a torn pectoral muscle in the season-opener at Buffalo last year. He didn't play again. Same for defensive end Patrick Kerney when he suffered the injury in 2006 with Atlanta.

"That's terrible, terrible news," Hasselbeck said when told of the season-ending nature of Tatupu's injury. "I don't know what to say."

Tatupu will become the second Seahawk placed on injured reserve. Offensive tackle Brandon Frye suffered a season-ending injury last week.

Seattle entered the season expecting to have one of the best linebacking trios in the league with Tatupu, Leroy Hill and Aaron Curry. Those three players were on the field together for no more than 10 total plays this year.

Hill suffered a groin injury in the third quarter of the season opener against the Rams. He has been out since, but was expected back for Seattle's next game which is at Dallas Nov. 1. He'll return to a lineup that will not include Tatupu.

David Hawthorne will replace Tatupu as Seattle's middle linebacker. Hawthorne is in his second year with Seattle, an undrafted player who made Seattle's team because of his big-hitting role on special teams.

He showed a great nose for the ball in his one start, which came against Chicago in Week 3. He finished with 16 tackles and intercepted a pass as Tatupu missed the game because of a sore hamstring, only the second game he's missed in his career.

But Tatupu is the nerve center of Seattle's defense, the one who receives the signal from the sideline and calls out the formation and play.