The Garden dropped from a crescendo to silence in Tuesday night’s third period, despite the Rangers heading toward their third straight victory, 4-2 over the division-rival Philadelphia Flyers. Marc Staal, the team’s top defenseman, writhed in pain on the ice, kicking his legs and holding his face as he bled from a Kimmo Timonen slap shot that deflected off Jake Voracek’s stick up into his right eye. Staal made it to the locker room, but the Blueshirts (11-8-2) — already playing without injured center Brad Richards (undisclosed) due to Patrick Kaleta’s boarding on Sunday night — cannot afford to lose the 26-year-old former All-Star. The Rangers said Staal had not been sent to the hospital as of early Wednesday morning but had no specific update on his condition. Staal missed 36 games last season due to a concussion, and there was also concern about his eyesight after such a frightening direct hit. “You can feel that it took the life out of the bench a little bit and the whole crowd,” said captain Ryan Callahan, who scored twice and added an assist. “It’s a scary moment.” The Rangers’ only hope that Staal returns from this injury quickly and in the same blistering fashion that power forward Rick Nash has from his four-game absence likely due to concussion symptoms.