You can't really call him a rookie because he's been a member of the Patriots for over two years, but Shawn Crable may as well be a rookie when it comes to expectations for him as a player -- he remains something of an unknown quantity.

The linebacker, a third-round draft pick in 2008 who has yet to play a regular-season down, was on the field yesterday with over 50 other teammates for an offseason workout in steamy conditions.

After, he said he was happy to be back and talked about his frustrating first two years.

"It feels good to be out there, get mental reps, taking your mind through the calls and stuff like that," said Crable. "I'm glad to be out there working with the guys and stuff like that instead of watching. I'm happy to be out there."

The former Michigan Wolverine, who has always looked more like a basketball forward than a linebacker, has put on some muscle with the extra time he's spent in the weight room. The extra bulk should help when he's going against tight ends and offensive linemen trying to get to quarterbacks.

Spending two years on injured reserve is "a frustrating process. When your mind is saying you can do something and your body is not reacting to it, it's a frustrating deal. But I got in the training room this year, worked with Mike (Woicik, the team's strength and conditioning guru), focused on my body, keeping me healthy so I can get out there and perform this year," Crable said.

If Crable can put his mental reps to work, there's certainly an opportunity for him this season: pass rush remains one of the biggest questions facing New England's defense.