Colorado @ San Francisco preview

Last Meeting ( Aug 10, 2012 ) Colorado 3, San Francisco 0

The Colorado Rockies can suddenly pitch - and that has spelled bad news for the top two teams in the National League West. The Rockies, whose 5.37 ERA is baseball's worst, have two shutouts in their last four games as they try for their fourth win in five contests Saturday against the host San Francisco Giants. Colorado, which was outscored 35-13 in a three-game sweep by San Francisco at Coors Field last weekend, shut out the Los Angeles Dodgers 2-0 on Monday and blanked the Giants 3-0 Friday. That loss dropped San Francisco into a tie for first place with Los Angeles in the NL West. The Giants fell to 1-8 in their last nine games at AT&T Park, during which they have scored only 19 runs.

Hunter Pence, who was acquired from the Philadelphia Phillies at the trade deadline, has been slow to adjust to his new surroundings. He is 6-for-39 (.154) in his first 10 games as a Giant with seven RBIs and 10 strikeouts. Matt Cain, who was honored by the Giants on Friday for pitching the franchise's first perfect game June 13, has lost two straight starts for only the second time this season. He will oppose Colorado rookie Drew Pomeranz, who hasn't won in five starts (0-3) but pitched four shutout innings at Los Angeles on Monday as the Rockies continue with their four-man rotation and about 75-pitch limit.

TV: 4:05 p.m. ET, Root Sports (Colorado), CS Bay Area (San Francisco)

PITCHING MATCHUP: Rockies LH Drew Pomeranz (1-6, 4.76 ERA) vs. Giants RH Matt Cain (10-5, 3.01)

Pomeranz allowed three hits, walked three and struck out seven at Los Angeles on Monday, but was lifted after 84 pitches. Colorado had lost Pomeranz's previous four starts. Pomeranz faced the Giants twice in his four starts last season and beat them 6-3 in his final outing of 2011. Pence hit a three-run homer in three at-bats against Pomeranz on July 15 while with the Phillies.

Cain hasn't completed six innings in two straight starts for the first time this season. He hasn't won since a 3-2 victory against Houston on July 15 and is 1-3 in his last eight outings, but has five quality starts during that span. Cain allowed five runs, eight hits and struck out seven in 5 2/3 innings in an 8-2 loss at St. Louis on Monday. He is 13-7 with 3.23 ERA in 26 starts against the Rockies. Colorado's roster is hitting .194 against Cain, with Carlos Gonzalez and Dexter Fowler a combined 7-for-45 with 17 strikeouts.

WALK-OFFS

1. San Francisco has won 13 of the last 17 meetings.

2. Giants SS Brandon Crawford was 2-for-3 on Friday and is batting .440 (11-for-25) against the Rockies this season.

3. Rockies 1B Todd Helton underwent successful hip surgery Friday. The 38-year-old is expected to be ready for spring training.