SAN FRANCISCO (AP) -- Jeremy Affeldt had another poor outing for the Giants. He's merely one example of how things have turned from bad to worse for the defending World Series champions.
Marlon Byrd's two-out grand slam capped a five-run eighth inning and the New York Mets beat San Francisco 10-6 on Tuesday for their third consecutive win.
Affeldt was charged with three of those runs and has given up nine earned runs over his last nine innings, a span of 13 games.
"We're giving up more runs than we're getting and I'm a big part of that," Affeldt said. "I really stink."
A day after needing 16 innings to top the Giants in a game that ended at 12:42 a.m., the Mets squandered leads of 3-2 and 5-3 but scored five times against the Giants bullpen to remain in control. Giants' relievers did not allow an earned run on Monday night.
"It seems like all the hard work is spitting in our face," Affeldt said. "We don't know what else to do but work hard, but it doesn't seem to be getting us anywhere."
The Giants did see some movement Tuesday -- downward. Thanks to San Diego's 2-1 win over Colorado, San Francisco dropped into fifth place in the NL West by percentage points.
The Giants haven't seen first place since May 26, when they started a 12-27 run that has put them on the brink of becoming an afterthought.
"We're being tested like we've never been tested before," Giants manager Bruce Bochy said.
Kensuke Tanaka, a veteran of the Japanese League, made his Major League debut a memorable one. He took away a likely home run from Andrew Brown to end the second with a catch above the left field fence. He pumped his fists and smiled as he raced back to the dugout.
"He's been around but he has that excitement when he plays," Giants starter Barry Zito said. "That's great and it's what we needed."
Tanaka also recorded his first big league hit -- a single in the fifth inning.
Omar Quintanilla had three hits for the Mets while Byrd and David Wright added two apiece. Wright drew a two-out walk before Byrd's home run off San Francisco reliever Jake Dunning.
Marco Scutaro singled twice for the Giants but was thrown out at home trying to score from first base on Pablo Sandoval's double in the first.
The Giants scored more than four runs for just the fourth time in 22 games but still lost and have the worst record in the majors (17-34) since May 13.
Scott Rice (4-5) retired one batter for the win as the Mets overcame a shaky outing by starter Dillon Gee. Gee allowed five runs and nine hits over 6 2-3 innings. He also walked five.
Carlos Torres pitched the final two innings and gave up Nick Noonan's pinch-hit RBI single in the ninth.
San Francisco's bullpen was also stellar in the extra-inning game on Monday but couldn't follow suit this time after the Giants scored single runs in three straight innings to tie the game at 5-all.
Anthony Recker committed an error in the second inning that allowed Hunter Pence to score San Francisco's first run. Pence reached on an infield hit leading off and took third on Brandon Belt's single before Recker threw wildly into center trying to catch Belt on an attempted steal.
The Giants went up 2-0 later in the inning but the Mets scored three times in the fourth to take the lead.
After Sandoval's run-scoring groundout in the fifth tied it at 3-all, Recker homered off Zito in the sixth to put the Mets ahead 5-3.
The Giants scored once in the sixth then tied it again on Sandoval's sacrifice fly in the seventh.
NOTES: Zito remained winless in his last seven starts dating to May 30. ... San Francisco placed backup catcher Hector Sanchez on the 15-day disabled list with a strained right shoulder. Pitcher Michael Kickham was called up from Triple-A Fresno and OF Cole Gillespie was designated for assignment. ... Veteran OF Jeff Francoeur agreed to terms on a minor league contract with San Francisco. ... RHP Matt Cain (5-5) faces former Giants prospect Zack Wheeler (2-1) in the series finale. Wheeler was the Giants first-round pick in 2009 when he was the sixth player taken overall.
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