Ryan Vogelsong (12-7 3.29) takes the bump for San Francisco, looking to get back on track after a rough start in his last outing. The right-hander lasted only 3.1 innings after allowing six runs early against the Diamondbacks, eventually taking the no decision. He is 1-0 with a 3.38 ERA against the Rockies this year.
Colorado will send out Alex White, (2-8 5.31), who hasn't won a game since June 3. He took the loss in his previous two outings, lasting 7.1 innings with three earned runs in both starts combined.
San Francisco is currently 30-20 against the NL West this year.
First pitch is set for 5:40 p.m. PT with coverage on CSN Bay Area and KNBR 680 AM.
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