Sickening moment NFL star Tommy Tremble appears to be knocked unconscious after brutal hit to the head

This is the horrifying moment Carolina Panthers player Tommy Tremble appeared to be knocked unconscious after suffering a sickening hit during Sunday's game against the Chicago Bears. 

Slow-motion replays showed the tight end hitting the ground and failing to immediately get to his feet after brutally colliding with Bears' Jaquan Brisker. 

The sickening scenes came with just under three minutes remaining in the first half, when Tremble reeled in what would be a nine-yard reception from quarterback Andy Dalton. 

Attempting to barge past Brisker, Tremble lowered his helmet, causing the two to brutal collided head-on. 

The Chicago safety brought down Tremble, who collapsed on top of Brisker and lay motionless. 

Tremble underwent evaluation for a concussion following the terrifying hit but was able to walk to the locker room under his own power. It is currently unclear if he will return to the game. 

The hit forced a fumble from the unmoving Tremble, who worryingly remained on the turf, as players from both teams trampled over him in an effort to recover the ball. 

More to follow.