Sanchez (7-6) was winless in his past 11 starts but tamed the Rockies with three runs on five hits plus seven strikeouts.
Colorado had eight hits, including four home runs. Troy Tulowitzki, Seth Smith and Carlos Gonzales connected for solo shots off Sanchez and Jason Giambi connected for a two-run homer in the bottom of the ninth off Leo Nunez, who held on for his 33rd save.
Jhoulys Chacin (9-10) took the loss after being roughed up in a four-inning start. Chacin surrendered five runs on eight hits and struck out four.