Rookie Brad Snyder put a big damper on the San Diego Padres' playoff hopes as the Chicago Cubs posted a 1-0 victory on Thursday at Petco Park.

The loss by the Padres (88-71) means they will have to travel and sweep the San Francisco Giants (91-75) in three games this weekend to force a one-game playoff for the National League West title on Monday.

The Padres trail the Atlanta Braves by two games (90-69) for the wild card. Atlanta, which has a magic number of two, hosts the Philadelphia Phillies over the weekend.

Jon Garland and two pitchers kept Chicago off the board until Aramis Ramirez led off the ninth with a bloop single to right field off San Diego closer Heath Bell (6-1), who had not lost since August 2009. Pinch runner Darwin Barney advanced to second on a sacrifice and scored when Snyder chopped a ball between third and shortstop for his fifth major league RBI.

Garland, who pitched seven scoreless innings in a 1-0 victory over the organization that drafted him earlier this season, was just as sharp Thursday. He retired 14 straight batters after a leadoff single in the first by Blake DeWitt. The 11-year veteran departed after 6 1/3 innings, yielding just four hits and a walk with eight strikeouts.

However, Cubs starter Tom Gorzelanny matched Garland frame-for-frame. He cruised until opening the sixth with two walks, but got Adrian Gonzalez, the NL’s leader in batting with runners in scoring position, to hit into a double play and retired the next hitter to escape. He departed after that frame, allowing three hits and four walks.

Sean Marshall (7-5) pitched the eighth for the win and Carlos Marmol closed out his third save of the series and 37th overall in the ninth.