Giants 4, Rockies 2: Buster Posey hit a two-run homer with two outs in the bottom of the ninth to cap a three-RBI night as San Francisco knocked off visiting Colorado.

Angel Pagan singled off Juan Nicasio (5-6) with one out and Posey came up two batters later and hammered a high fastball over the left-field fence for his second career walk-off blast to give manager Bruce Bochy his 1,600th career victory. The Giants remained five games behind the Los Angeles Dodgers in the National League West and possess a 1 1/2-game lead over Atlanta and Pittsburgh for the second wild card.

Rockies first baseman Justin Morneau stroked a game-tying double in the top of the ninth off Giants closer Santiago Casilla (2-3) to tie the score at 2-2. San Francisco starter Tim Hudson allowed one run and four hits in eight innings and struck out eight to raise his career total to 2,002.

Colorado reliever Nick Masset walked two batters in the seventh before Posey – who went 3-for-5 – lined a full-count single to left off Brooks Brown to give the Giants a 2-1 lead. Rockies starter Franklin Morales gave up one run and seven hits in six innings.

San Francisco took a 1-0 lead in the fourth when Matt Duffy doubled, moved to third on a single by Joe Panik and scored on Gregor Blanco’s safety-squeeze bunt single. Colorado tied the game when Corey Dickerson homered into McCovey Cove to lead off the fifth for Colorado’s first hit off Hudson.

GAME NOTEBOOK: Dickerson’s homer was the 100th of the “splash” variety since AT&T Park opened in 2000. … San Francisco backup C Hector Sanchez is still experiencing severe concussion symptoms and will likely miss the rest of the season. … Colorado placed C Wilin Rosario (wrist) and LHP Boone Logan (elbow) on the 15-day disabled list and recalled C Jackson Williams and LHP Christian Friedrich from Triple-A Colorado Springs.