Jadeveon Clowney said Thursday he suffered a concussion during a preseason practice against the Denver Broncos.

The No. 1 overall pick of the 2014 NFL draft missed the Texans’ final two exhibition contests, including an 18-17 road victory against Denver on Aug. 23.

Clowney exited an Aug. 20 practice against the Broncos early. He was seen shaking his head on a trainer’s table after taking off his pads.

“It was a head thing,” said Clowney, prior to practice Thursday at NRG Stadium.

Clowney said it took him almost two weeks to get over the concussion.

“It was just something that happened on the field in Denver. So we’ve moved on to Washington now,” said Clowney, who acknowledged he previously dealt with a concussion before joining the Texans.

The former South Carolina star was not on the Texans’ injury report Wednesday and has been cleared for the Texans’ regular-season opener Sunday against the Washington Redskins at NRG Stadium.

Texans coach Bill O’Brien said Clowney will start at weakside outside linebacker in his NFL debut.

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