San Francisco (59-77) at Colorado (64-74)

The Colorado Rockies should feel quite familiar with the position they’re in.

Last season, the Rockies overcame a five-game deficit in September to reach the playoffs and claim their first pennant. They’re nearly in the same situation this year.

The Rockies look to get the month off to a strong start Monday night when they open a three-game set with the San Francisco Giants for the second time in a week.

Colorado (64-74) is third in the West, 3 1/2 games behind second-place Los Angeles and six behind first-place Arizona, which was tied with San Diego atop the division entering last September. For the Rockies, it’s one game worse than where they were a year ago before they capped a season-ending 21-8 run with a victory over the Padres in a one-game playoff for the wild card.

Colorado has 24 games left this season, and hopes a pair of tough losses to the Padres didn’t hamper their chances at another late comeback. On Sunday, Colorado lost 2-1 at San Diego on a walk-off single by Luis Rodriguez, less than 24 hours after falling 9-4. Those defeats followed a 10-3 run that put the Rockies back in the division race.

“Every loss is difficult, but you run out of games and they have more meaning,” Rockies manager Clint Hurdle said.

The Rockies hope another series with the Giants (59-77) can help boost their playoff chances. Colorado won Monday and Tuesday at AT&T Park before dropping the finale 4-1, evening the season series at six wins apiece.

Jorge De La Rosa (7-7, 5.60) helped Colorado to a 7-2 victory over the Giants on Tuesday, yielding two runs - one earned - and five hits in six innings. In six games last month, including two relief appearances, the left-hander is 2-1 with a 2.22 ERA.

“He stayed under control,” Rockies catcher Chris Iannetta said of De La Rosa on the team’s official Web site. “He made some adjustments and was able to battle through some early problems.”

Garrett Atkins has been key for Colorado of late, going 9-for-23 (.391) with two homers and seven RBIs in the last five victories. However, the infielder is 0-for-9 in the last three defeats.

San Francisco has dropped five of its last seven games after getting swept at Cincinnati over the weekend, including a 9-3 defeat on Sunday.

“We stunk this weekend,” Giants manager Bruce Bochy said. “We know it. It was tough pitching this series. We were having a good month, but the way it ended wasn’t. They had been struggling, but we certainly woke up their bats in this series.”

Bochy will now turn to Jonathan Sanchez (8-9, 4.53), who is expected to be activated from the disabled list Monday after missing three weeks with a strained left shoulder.

The left-hander’s last outing came on Aug. 11, when he allowed two runs and five hits in seven innings while the Giants’ offense struggled in a 3-1 loss. He’s 0-5 with a 6.82 ERA in seven starts since his last victory June 29 at Oakland.

Sanchez is 1-0 with a 5.82 ERA in three starts against the Rockies this season. That victory came in his last start against them on June 12 at Coors Field, as he was tagged for seven runs and nine hits in five innings of a 10-7 win.