Miami receiver Grant DuBose was taken off the field on a stretcher after a helmet-to-helmet hit against the Houston Texans on Sunday.Related video above: Maine high school football player pledges to donate brain to science to help improve game safetyDuBose tried to make a catch in the third quarter but was hit in the head by rookie Calen Bullock before his head violently hit the turf. He appeared to clench both fists after the hit — movements consistent with what's referred to as the "fencing response," which can be common after a traumatic brain injury — before remaining motionless as medical personnel rushed to his side.Bullock was given a flag for unnecessary roughness for hitting a defenseless receiver on the play.DuBose remained on the field for more than 10 minutes as he was tended to by emergency medical personnel. His jersey was cut off and a neck brace was put on him while players from both teams watched with concern.At one point, while he was down, the Dolphins moved away from him and into a circle where they kneeled and appeared to be praying. Miami coach Mike McDaniel and Houston coach DeMeco Ryans embraced at one point while he was still on the field.DuBose was eventually put on a spine board where his arms and legs were strapped down, and he was taken off the field. A tube of some kind was in his mouth, and no movement could be seen as he was taken off the field.The Dolphins said DuBose has been ruled out with a head injury. He is in stable condition and is being taken to a local hospital for further evaluation.DuBose was a seventh-round pick last season and returned Sunday after injuring his shoulder early in the season.It's the second straight Texans game where an opposing player has been injured by an illegal hit to the head after linebacker Azeez Al-Shaair's hit to the head of a sliding Trevor Lawrence gave the quarterback a concussion on Dec. 1.Lawrence was scrambling in the second quarter of that game. He initiated a slide before Al-Shaair raised his forearm and unleashed on the defenseless quarterback. He also displayed the "fencing response" but soon got up on his own power and walked to a cart, which took him off the field.Al-Shaair was ejected for the hit and given a three-game suspension, which was upheld on appeal.