RENTON, Wash. -- A lot of surprising things happened Monday night at St. Louis, but maybe the biggest shocker was seeing linebacker Bruce Irvin do his cornerback imitation.

And it was a good one, coming up with an interception on a deep sideline pass, just like his buddy Richard Sherman often does.

Irvin was step-for-step with Rams receiver Brian Quick, who came out of the backfield to force Irvin to cover him on a speed route outside. Irvin was right there for the pick, not bad for a guy who was seen only as a pass-rushing specialist.

“I played quarterback in high school,” Irvin said. “I just waited for my opportunity to show I could be more than a rush end.”

The Seattle Seahawks gave him that chance by moving him from defensive end to linebacker this season. But Irvin missed the first four games while suspended for violating the league's performance-enhancing-drugs policy, so no one knew for sure how the move would work out.

A lot of doubts about Irvin’s ability to play linebacker were erased in St. Louis when he had nine tackles, a sack and a forced fumble to go with his surprising interception.

“Bruce had a fantastic game for us,” Seattle coach Pete Carroll said. “He was all over the place. He just looked really comfortable playing the position and all of the different things that we’re doing with him.

"If there was a thought that this was an experiment at one time, it’s totally working out and we’re really excited about what he’s doing. He’s a gifted athlete.”

The Seahawks took a lot of criticism when they drafted Irvin in the first round last year. Many experts said it was a reach and a gamble on a player who had a troubled past before he made it to West Virginia as a major college player.

“But Pete has recruited me out of junior college,” Irvin said. “He saw a kid that had a lot of baggage and personal issues, but a guy that if he surrounded him with a lot of positive things, he could get great production out of him. I will always thank Pete for taking a chance on me. He believed in me, and that means a lot.”

Irvin was seen as a bit of a ‘tweener’’ by many draft experts – too small to play defensive end and too bulked up to play outside linebacker.

“In the process of him getting prepared for the draft, some scouts worked him out at linebacker,” Carroll said. “The results were them saying he doesn’t have what it takes to play linebacker. They said he was uncomfortable with it and a fish out of water.”

Irvin doesn’t remember that workout, but Carroll never believed it, anyway.

“I heard that and I totally dismissed it,’’ Carroll said. “I’d already seen him do stuff that was like a defensive back playing defensive end. He showed those things in college, so I didn’t buy into that. I don’t know what happened in that workout, but it must have been horrible. I can’t imagine the drills they put him through that would show that.”

Seattle linebackers coach Ken Norton agreed with Carroll and wanted to give Irvin a shot this season at moving to linebacker. Irvin is thankful for the chance. He felt his days were numbered as a defensive end.

“In order for me to keep up with those huge linemen, I would need to put on 20 or 30 pounds,” Irvin said. “I’m a speed guy. Playing linebacker gave me the chance to use my speed and make plays. I tell Ken Norton every day, ‘You saved my career making me a linebacker.’ I just want to keep working hard so he’ll know he made the right decision.’’

That seems obvious now, but an interception on a deep sideline route was more than anyone expected. Irvin said he got a little help on that play from free safety Earl Thomas.

“He told me to look out for the wheel route,” Irvin said. “I really look up to Earl. He’s our leader out there.”

Irvin’s teammates believe in him. So do his coaches. A cornerback-like interception on a deep pass was a bonus.

“That was my first one ever like that,” Irvin said. “I think this shows I’m capable of doing more than just coming in on third down to rush the passer. I like to prove people wrong.”