St. John’s Prep graduate Jonathan Goff, a former Lynn resident, started at middle linebacker for the New York Giants in their preseason opener against the New York Jets in the inaugural game at New Meadowlands Stadium on Monday.Veteran linebacker Keith Bulluck missed the game with a knee injury. The Giants defeated the Jets, 31-16.Goff, 24, a third-year member of the Giants who played college ball at Vanderbilt, made his mark early in the game by thwarting a pass to Jets tight end Dustin Keller. He found stopping the run to be tougher, although he caught a break when a holding penalty wiped out an apparent Jets touchdown carry. The 6-2, 236-pound linebacker finished the game with two tackles.The game had a scary moment for the Giants when quarterback Eli Manning suffered a three-inch laceration on his forehead that required 12 stitches. X-rays were negative and Manning had no signs of a concussion.