HOUSTON -- Jadeveon Clowney returned to practice on a limited basis Monday for the first time since microfracture knee surgery. The Houston Texans, however, aren't sure when he'll play in a game.

Clowney was the top overall pick in last year's draft. He played just four games last season because of various injuries before having season-ending surgery in December.

On Monday the outside linebacker participated in walk-throughs and individual drills, but did not do any contact work.

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Coach Bill O'Brien says: "We're going to ease him back into this thing and ramp him up to be able to play in games." Clowney discussed the months of rehabilitation and says he still has "a little ways to go, but we're heading in the right direction."