MLB: Colorado 4, San Diego 1

SAN DIEGO, Sept. 12 (UPI) -- A three-run double by Yorvit Torrealba in the ninth inning kept alive Colorado's late-season surge Friday and lifted the Rockies to a 4-1 win over San Diego.

Five San Diego pitchers had combined to hold Colorado scoreless on three hits over eight innings, but the Rockies rallied for four runs in the ninth to win their eighth straight game.

The Rockies remained two games behind the Los Angeles Dodgers for the National League West lead and moved 5 1/2 games in front of San Francisco for the top spot in the wild-card chase.

Closer Heath Bell (4-3) was called on to protect the one-run advantage in the ninth, but he loaded the bases on a walk to Todd Helton, a single by Brad Hawpe and a walk to pinch-hitter Jason Giambi.

Bell then got Matt Murton on strikes for the second out of the inning and had a 2-2 count on Torrealba before the Colorado catcher cleared the bases with a drive to deep left-center. A single by Paul Phillips brought in Torrealba with the fourth run of the inning.

Rafael Betancourt (5-3) got the win by retiring the final two batters in the eighth inning. After Colorado rallied, Franklin Morales worked a perfect ninth for his sixth save.