With 1:15 remaining in the second quarter and the Spurs leading 45-36, Barnes came from the weakside to defend a drive by Boris Diaw. Barnes wound up catching his legs on Diaw's midsection and fell headfirst back to the court. He landed hard on his right arm and shoulder and the right side of his head hit the court. Diaw, meanwhile, was called for travelling on the play.
Barnes then lay motionless on the court for an extended period of time and was quickly surrounded by his teammates and coaching staff on the court. He eventually left the court walking under his own power, but appeared a bit wobbly and he was bleeding from the right side of his head.
After remaining in the locker room until halftime, the rookie forward made a remarkably return to the court to start the second half. The Warriors announced early in the third quarter that Barnes had received six stitches to patch up a laceration over his right eye.
He was later removed from the game during the fourth quarter after he complained of headaches and the Warriors announced he would not return.
Warriors coach Mark Jackson told reporters after the game that Barnes passed a concussion test at halftime before reentering the game.
"He was alert when he was on the floor," Jackson said. "He walked off on his own. We have a great staff with our doctors and our trainers and he gave it a go. He actually played well, but it ran its course."
San Antonio went on to win the game 94-82 to eliminate Golden State from the playoffs in six games. The Spurs now advance to the Western Conference finals, where they will face the Grizzlies. Barnes, 20, is averaging 16.7 points, 6.6 rebounds and 1.3 assists during the 2013 playoffs. He averaged 9.2 points, 4.1 rebounds and 1.2 assists during the regular season.