SAN ANTONIO — Cowboys receivers coach Jimmy Robinson has been released from a San Antonio hospital after he was knocked unconscious earlier Saturday after being hit on the sidelines by receiver Teddy Williams during a punt drill.Trainers and medical staff attended to Robinson immediately, and he was taken to the San Antonio hospital.Robinson, 58, who was unconscious for about a minute, was to undergo tests at the hospital, Cowboys spokesman Rich Dalrymple said.Practice continued for a short time after the collision, but it was stopped when Cowboys players and coaches became concerned.Robinson, 58, had been facing upfield at the punt drill and did not see Williams, who had gotten away from a defender and began accelerating up the sideline. Williams did not have time to stop before he hit Robinson chest-to-chest. The coach fell to his back and hit his head on the turf at the Alamodome.Robinson is in his first season with the Cowboys. He was hired from the Green Bay Packers in February by coach Jason Garrett and also given the title assistant head coach. The two worked together with the New York Giants 10 years ago.The hit to Robinson shook up the Cowboys. Garrett, several coaches and players came to the sideline where Robinson was being cared for, and practice was stopped briefly.Williams, a 6-foot-3, 200-pound first-year undrafted free agent from Texas-San Antonio, did not have time to stop before he hit the coach, but he appeared to attempt to hold up before the collision. The two fell to the ground together, but Williams did not fall on Robinson. The player got to his feet quickly and returned to the field.Later, after Robinson had been taken off the field, Williams left the field with a trainer, appearing to favor his left leg.Two years ago, another Cowboys assistant coach was injured on the job. Former special teams coach Joe DeCamillis suffered broken vertebrae when the Cowboys practice facility collapsed during a rookie camp in a 2009 storm.