The Giants' offense picked up where it left off from Tuesday's historic blowout, but the outpouring of runs eventually stopped and their pitching staff couldn't fend off the Rockies.

San Francisco missed a chance to climb back to .500 for the first time since Aug. 2 after blowing a five-run lead in a 9-6 loss on Wednesday afternoon that sealed a disappointing split of its two-game series at Coors Field.

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The defeat dropped the Giants to 18-20 on the season, a half-game behind the Rockies in the National League West and for the eighth and final playoff spot in the NL. They'll now head back to the Bay Area to begin their penultimate homestand of the year against the D-backs and Mariners, who both emerged as sellers at the Trade Deadline.

The Giants took two of three from the D-backs last weekend, and their NL West foes will look markedly different after jettisoning Starling Marte, Robbie Ray, Archie Bradley and Andrew Chafin on Monday. One familiar face remains, though: Madison Bumgarner, who is expected to be activated off the injured list and make his first start against his former club on Saturday.

Still, the Giants are keeping their focus trained on the present, not the past. With only 22 games left to play, their margin for error is growing increasingly slimmer, and they missed a huge opportunity to advance their playoff push on Wednesday.

"The ball's in our court," manager Gabe Kapler said. "We have the ability to control our destiny. Today's loss was disappointing. At the same time, we're swinging the bats really well. We've got a lineup that can put up runs, Coors Field or not. And we can do that against righties and lefties. And what we're starting to see is our starters are giving us a chance to win games. Outside of today, our bullpen has been pretty good as well.

"We need it all to come together in these last couple of weeks. I think our schedule is a manageable one."

Less than 24 hours after matching San Francisco records by scoring 23 runs on 27 hits, the Giants continued to roll by scoring four runs in the first inning on a solo home run by Mike Yastrzemski and RBI singles from Alex Dickerson, Joey Bart and the newly acquired Daniel Robertson.

The Giants pushed their lead to 6-1 after Robertson drew a bases-loaded walk in the fourth, but the Rockies began to claw back by scoring once in the fifth and twice in the sixth to chase rookie Logan Webb, who was charged with four runs over 5 1/3 innings.

The Giants took a 6-4 lead into the seventh, but the Rockies erased the deficit by erupting for five runs off relievers Sam Coonrod and Tyler Rogers. Coonrod, who had worked 3 2/3 scoreless innings since returning from the injured list last month, issued a leadoff walk to Trevor Story and gave up a single to Nolan Arenado to put runners on the corners for Charlie Blackmon, who brought Colorado within one with an RBI double to center field.

Former Giant Kevin Pillar followed with a two-run triple off Rogers to put the Rockies ahead, 7-6, and Sam Hilliard capped Colorado's rally with a two-run homer to left field.

"These guys aren't going to be perfect," Kapler said. "They're going to make mistakes. They're going to miss with their location. That's going to happen. Those guys came into the game and they just weren't able to locate their pitches. It's part of baseball."

The bullpen emerged as one of the Giants’ biggest flaws earlier this year, but the group appeared to turn a corner after rebounding to post a 1.38 ERA over the previous 12 games.

Giants president of baseball operations Farhan Zaidi explored deals for a right-handed reliever at the Trade Deadline to bolster his relief corps, but he ultimately couldn’t find a match that made sense for the club. He said the resurgence of Coonrod and Trevor Gott factored into his decision to not bring in reinforcements, though Coonrod couldn’t validate that faith on Wednesday.

"If you want to win here in Colorado, you've got to keep scoring just like we did yesterday," first baseman Wilmer Flores said. "You know how the games are here. Even if we scored a couple in the first and second inning, we've got to keep scoring. But we didn't, and we lost the game."