The Houston Texans fear that outside linebacker and number-one pick in this year's draft Jadeveon Clowney suffered a torn meniscus in Sunday's game against the Washington Redskins. The injury could require arthroscopic surgery, according to ESPN.

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Clowney landed awkwardly on the ground in the second quarter and left the game. He did not return in the second half as the Texans won, 17-6. He recorded one tackle for a loss of nine yards before suffering the injury.

Initial reports said Clowney suffered an MCL injury. Bleacher Report stated he could miss four to six weeks, but he will undergo further testing on Monday. Texans coach Bill O'Brien seemed to be optimistic about the diagnosis, as it could have been worse.

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"We're consulting with doctors and trainers right now," O'Brien said after the game. "I'm not sure about the status, but I will say right now that they think it's a good prognosis, so it looks like he's going to be OK. He may miss some time, he may not. Who knows? We'll know better as the week goes on."

The Houston Chronicle reported that former first-round pick Whitney Mercilus will start in Clowney's place. Houston fans were hoping to see Clowney paired with former NFL Defensive Player of the Year J.J. Watt, and the duo looked good during the preseason. Clowney's upside is extremely high, so it's likely the Texans coaching staff would remain cautious with the rookie so early in his career.