SAN DIEGO (AP) — With the playoffs fast approaching, the last thing the San Francisco Giants wanted to see was star catcher Buster Posey hunched over on his knees behind home plate.A leading contender for NL MVP, Posey gave the Giants a scare when he took a wild pitch off his throat and was in plenty of discomfort. But he stayed in the game and increased his lead in the batting race to help the NL West champions beat the San Diego Padres 3-1 Friday night.“It does show you how tough he is. It was a full shot on his …