MLB: Colorado 6, Pittsburgh 5

PITTSBURGH, April 10 (UPI) -- Sean Smith drove in the go-ahead run with a bases-loaded walk Sunday and the Colorado Rockies hung on for a 6-5 victory over Pittsburgh.

Trailing 5-4 entering the seventh, the Rockies rallied for a pair of runs after two outs. Dexter Fowler singled off Pirates starter James McDonald to begin the comeback.

Mike Crotta (0-1) entered the game and issued a walk to Jonathan Herrera. Jason Giambi followed with an RBI single to forge a 5-5 tie and Crotta then yielded back-to-back walks to Troy Tulowitzki and Smith to force in the decisive run.

Smith also had an RBI single and Jose Lopez bashed a three-run homer for the Rockies, who took three of four games against the Pirates and improved to 6-2.

Jhoulys Chacin (2-0) earned the victory, allowing five runs (four earned) on seven hits over six innings and Huston Street picked up his fourth save with a scoreless ninth.

Lyle Overbay drove in two runs for Pittsburgh.