In San Francisco, they never stopped calling him M-V-Posey. But these days, you can expect the chants to be a little louder when Buster Posey excites the fans at AT&T Park. The San Francisco Giants are right back in contention in the NL West again, after falling as many 5 1/2 games behind the Los Angeles Dodgers just a few weeks ago. And Buster Posey, their franchise cornerstone, has been a huge part of their resurgence. The Giants beat the Detroit Tigers again Saturday , their second straight win in Detroit. Posey was 3-for-3 with a homer and two runs scored. In Friday's win , Posey was 2-for-5. He's had at least two hits in each of his last five games and that's certainly one of the reasons the Giants are within two games of the Dodgers again. Before this week, they hadn't been within two since the start of August.