CINCINNATI (AP) -- Sean Marshall often goes to his curveball as an out pitch.
It didn't work that way against Angel Pagan.
Pagan hit a hanging curve for a three-run homer in the ninth inning, lifting the San Francisco Giants to a 6-5 win over the Reds on Thursday.
"The curveball's been a good pitch for me," said Marshall (0-2), who had his first blown save after converting four opportunities. "I've gotten some outs with it. The ball hung in the middle of the plate. He didn't get a good swing on it. What hurts is the guys played so well."
Marshall, acquired from the Cubs during the offseason and moved to closer in spring training after Ryan Madson was lost to season-ending elbow-ligament replacement surgery, struggled from the beginning of his second outing in less than 24 hours.
He walked Joaquin Arias to lead off the ninth, and Ryan Theriot followed with a single. After pinch-hitter Brett Pill struck out, Pagan lofted a 1-2 pitch 386 feet into the left field seats to snap the Giants' losing streak in Cincinnati at seven games.
The homer came on the first pitch after Pagan took what many in the crowd of 17,317 thought was strike three.
"I didn't hit my spot with it," the left-hander said. "It was borderline. The next pitch was the one that mattered."
Manager Dusty Baker couldn't tell from the dugout if the pitch was a strike, but he knew Marshall wasn't as sharp as he had been.
"That leadoff walk gets you into trouble," Baker said. "That curveball (to Pagan) kind of rolled. It's tough. He only gave up one home run all of last year (in 78 appearances). You hope history repeats itself."
Javier Lopez (2-0) allowed two hits but no runs in the eighth to earn the win. Santiago Casilla struck out the side in the ninth for his second save in two opportunities.
Jay Bruce hit a two-run home run in the sixth inning and Scott Rolen led off the seventh with his second of the season, both in the last two games, giving starter Homer Bailey a shot at evening his record at 2-2.
Bailey lasted 6 1-3 innings, allowing seven hits and three runs -- two earned -- with two walks and six strikeouts.
"I had some quick innings," said Bailey, who also had a run-scoring single in the second inning. "The fastball and (split-finger) were working, and I was able to get some groundballs and some quick outs. I really felt like I should have put up a zero in the last inning, so in a roundabout way, I think I should've done a lot better than I did."
Giants third baseman Pablo Sandoval went 1 for 5, extending his season-opening hitting streak to 19 games, a franchise record. He went into the game tied with Johnny Rucker, who hit in the first 18 games of the 1945 season with the then-New York Giants.
Giants starter Ryan Vogelsong gave up seven hits and four runs with two walks and five strikeouts in six innings.
The Reds took a 2-0 lead in the second on Devin Mesoraco's sacrifice fly and Bailey's RBI single. The Giants capitalized on shortstop Zack Cozart's error to tie the score with two runs in the fourth inning. Bruce broke the tie with his fourth homer of the season, a 381-foot shot to right-center field that just cleared the glove of the leaping Pagan. The homer was Bruce's first since hitting two against the Miami Marlins on April 8.
Pinch-hitter Gregor Blanco came up with a sacrifice fly to cut Cincinnati's lead to 4-3 in the seventh before Rolen's 429-foot homer.
NOTES: Marshall's appearance was the 300th of his career. ... The Giants hadn't won in Cincinnati since a 3-0 win on June 8, 2010. ... Pagan extended his hitting streak to 11 games (16 for 52, .308) with a seventh-inning single. ... Giants C Buster Posey went 0 for 3 with a walk to see his hitting streak snapped at eight games. ... San Francisco RF Nate Schierholtz went 0 for 4 to extend his streak of consecutive hitless at bats to 12.
