In his first 23 starts of the season, Jake Peavy had one win.
But behind two superb outings in his last two starts, Peavy has collected a pair of wins, marking the first time since September 2013 that he has won back-to-back decisions.
Peavy will take the mound Monday night against the Rockies as the Giants try to cling to a one-game lead for the National League's second Wild Card spot. The Giants have lost just one of their last four series, to the sizzling Nationals over the weekend.
In his last two starts, Peavy has posted a 1.93 ERA and a 11-to-3 strikeout-to-walk ratio in 14 innings. He four-hit the White Sox across seven innings before scattering 10 hits in seven innings against the Cubs.
In his career, Peavy has struggled against the Rockies, going 5-6 with a 4.10 ERA in 19 starts against Colorado. But since 2008, Peavy has only faced the Rockies twice.
Unlike Peavy, Rockies left-hander Tyler Matzek will be riding a losing streak into Monday's matchup. Matzek has lost his last five decisions across four starts and an emergency relief appearance.
The five-game stretch has inflated Matzek's ERA from 4.28 to 5.38 and dropped him from 2-4 to 2-9. He has an 8.06 ERA and 1.881 WHIP in that span while opponents are slashing .326/.415/.618.
In his last game Tuesday against Kansas City, he gave up three runs in 6 2/3 innings and lost, 7-4. That was his longest outing since he went a career-high seven innings in his Major League debut June 11 against Atlanta and July 26 against Pittsburgh. He has pitched at least six innings in nine starts this season.
The Giants are the only division opponent Matzek has not faced. He is 0-4 against the Dodgers, Padres and D-backs.
Rockies: Rosario to return Monday?
Catcher Wilin Rosario was held out of the lineup again Sunday, one night after not being available to pinch-hit during Saturday's 13-inning game.
Rosario planned to hit in the indoor cages Sunday and hoped to return for Monday's matchup.
He last played Wednesday against Kansas City, when he hurt his wrist sliding.
Giants: Lincecum may skip next start
Tim Lincecum's status for his next scheduled start remained uncertain Sunday, as Giants manager Bruce Bochy had yet to meet with the right-hander to discuss his slump.
Bochy said he had talked with pitching coach Dave Righetti and general manager Brian Sabean about Lincecum, who yielded six runs (four earned) in 2 2/3 innings Saturday. Lincecum is 1-3 with a 9.49 ERA in his last six starts.
Bochy added that Yusmeiro Petit, the leading candidate to start Thursday against Colorado if Lincecum doesn't, will need a couple of days' rest after pitching 6 1/3 innings in two appearances since last Thursday. But Bochy said once Petit's arm recovers, he wouldn't hesitate to use the long reliever in a game if the need for him arose.
• The Rockies are a Major League-worst 18-44 on the road this season. Monday's game starts a seven-game road trip for Colorado.
Matthew DeFranks is an associate reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.