TJ Watt enters concussion protocol after sickening knee to the head in the first quarter of Thursday's Steelers loss to Patriots - despite returning and playing most of the game for his team

Pittsburgh Steelers pass-rusher T.J. Watt has entered concussion protocol after playing on from a sickening knee to the head in Thursday night's loss to the Patriots.

Watt was hurt on the first play of Thursday's game - running back Ezekiel Elliott hit him with knee as Watt dived towards him at the end of his run.

The 29-year-old Watt left the field for a number of snaps but ultimately returned in the first quarter for his team and by the end of the game had played 90% of the defensive snaps.

According to the Steelers, Watt reported symptoms Friday morning and he will have to be cleared by an independent neurologist before he can return to action.

The Steelers next play on Saturday, December 16 against the Colts.

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