Chris Hassel of ESPN had the details from when Sanchez initially injured his shoulder:
Sanchez knocked out of game with apparent right shoulder injury. Pads are off. He's done for the game. #Jets— Chris Hassel (@hasselESPN) August 25, 2013
Geno Smith has helped lead the Jets to a 3-2 start, after knocking off the Falcons on Monday Night Football. Sanchez's future role with the Jets remains to be seen.