IRVING (CBSDFW.COM) -- A visibly and audibly frustrated Sean Lee was escorted off the Valley Ranch practice field during Tuesday's opening of Dallas Cowboys OTAs, a continuation of the injuries that have plagued the potential star middle linebacker.
Lee collided with rookie offensive lineman Zack Martin during the non-contact workout, injuring his left knee. Medical personnel tended to his leg and foot area before guiding him into the locker room. During that walk, the mild-mannered Lee lashed out at photographers jostling for position, asking loudly for "respect."
Last August, Lee, 27, signed a six-year contract extension worth as much as $51 million -- an incentive-heavy deal built to account for the fact that since entering the NFL in 2010, Lee has yet to play a full season.
"I haven't been healthy the last couple of years, and I know it's my job to be on the field," Lee said recently. "The key now is to be on the field for the entire year and contribute the entire year."
Lee appeared in just 11 games for the Cowboys in 2013, missing the final three games with a torn ligament in his neck, but entered the offseason program healthy.
Cowboys head coach Jason Garrett said very little about the injury following the team's practice, only saying that Lee's left knee will be examined by a doctor this afternoon.
"Unfortunately he's had to deal with a few of these things, but he's as mentally tough an individual as I've ever been around," said Garrett. "Whatever the circumstances are, he always puts his best first forward and strives to be his best. Don't anticipate this being any different."
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