Nicasio (4-1) broke a personal three-start winless streak, taming the Giants on three hits. The right-hander walked one and struck out five in the victory.
Carlos Gonzalez and Troy Tulowitzki each provided a pair of RBI and Dexter Fowler went 4-for-5 with two runs scored for the Rockies, who forged a first-place divisional tie after taking three straight from the Giants at Coors Field.
San Francisco's Barry Zito (3-3) was tagged with the loss, surrendering five runs on 11 hits over 5 2/3 innings.
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