Lewis, whom the Lions drafted in the fourth round, can be a pass-rushing defensive end or a stand-up outside linebacker.
"I feel comfortable both ways," he said Saturday. "Wherever coach puts me is where I'll play and be happy as long as I get the opportunity."
Detroit selected Lewis 125th overall with a pick acquired by trading the No. 117 pick to San Francisco for the 49ers' fourth-round pick and their sixth-round selection, 196th overall.
The 6-foot-1, 253-pound Lewis started nine games last season as a defensive end and played in 10 for the Sooners, making 13 tackles for losses, including 5.5 sacks, and finished with 60 tackles. He missed the last three games of the season because of a sprained ligament in his left knee.
The native of Dewar, Okla., skipped his senior season after making 119 tackles, including 10 sacks, in 34 games.
The Lions didn't start the draft with a six-round pick because the NFL took it away because of a tampering charge involving Kansas City.
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