Updated

Rookie lefty Eric Surkamp makes another start on the fringes of the playoff race tonight as the defending World Series champion San Francisco Giants visit Coors Field for the third of four games against the host Colorado Rockies.

The Giants pounded out 13 hits en route to a 9-1 pummeling of the Rockies in game two on Friday and pulled within five games of the Atlanta Braves in the chase for the National League's wild card playoff berth.

San Francisco is six games behind Arizona in the NL's West Division.

Cody Ross, Brandon Belt and Chris Stewart all homered and Aubrey Huff picked up three hits, including a double, for the Giants, who have won six straight.

Madison Bumgarner (12-12) gave up one unearned run on six hits over seven innings while fanning three and walking one. He also contributed offensively with a pair of hits.

Jordan Pacheco had three hits, Thomas Field picked up two hits and Wilin Rosario scored the only run for the Rockies, losers in three of their last four games.

Alex White (2-2) lasted 5 2/3 innings, giving up six runs on nine hits while striking out three and walking three.

Surkamp, a 24-year-old from Cincinnati, was a sixth-round pick of the Giants in 2008 and reached the majors on Aug. 27, when he tossed six innings of one- run ball for a no-decision in the Giants' 2-1 win over Houston.

He returned to beat San Diego on the road on Sept. 6, then did the same thing at home six days later to improve to 2-0.

In 16 2/3 innings, he's allowed 18 hits and six earned runs while walking five and striking out six.

Surkamp was 10-4 at Double-A Richmond and 1-0 at Single-A San Jose this season before the call-up to the big leagues, posting a 1.94 earned run average across 148 1/3 innings.

Going for the Rockies is another rookie lefty, 22-year-old Drew Pomeranz, who makes his second big-league start.

The fifth overall pick of the Cleveland Indians in 2010, Pomeranz came to Colorado as part of the trade deadline deal for Ubaldo Jimenez in July.

He debuted on Sept. 11 against Cincinnati and was superb, allowing just two hits in five scoreless innings of a 4-1 victory.

Pomeranz, a native of Memphis, Tenn., was 4-3 with three minor-league teams and had a 1.78 ERA in 101 innings before his promotion.

San Francisco has won nine of 13 versus Colorado this year and 13 of the last 18 meetings overall.