NEW YORK (AP) -- The Kansas City Royals are getting a healthy dose of National League baseball on their first trip to Citi Field.
While some of them are familiar with that style of play, they are a bit out of practice with it.
Royals manager Ned Yost found the perfect time to use pinch-hitter Jason Maxwell, and he responded with the tiebreaking homer in the 12th inning to lift Kansas City to a 4-3 victory over the New York Mets on Saturday.
Kansas City squandered a two-run lead in the eighth inning, but got back to a winning way just one day after its nine-game winning streak was broken.
''I got ready like three different times,'' the newly acquired Maxwell said of his fifth major league pinch-homer and first of any kind since joining the Royals last week from Houston. ''I think it helps that I have experience in this situation. My first home run was a pinch-hit grand slam, and I hit three pinch-hit home runs last year.''
Maxwell homered deep into the left-field seats leading off the 12th for the Royals, who improved to 8-2 in extra innings after losing in the 11th on Friday.
Maxwell hit a 3-2 pitch from David Aardsma, who had fallen behind 3-0. The New York bullpen had been perfect after starter Jeremy Hefner left after six innings, but Aardsma couldn't retire the first batter he faced.
''You can't get behind like that because then you have to give him something to hit,'' Aardsma said.
The Mets lost hours after putting All-Star third baseman David Wright on the disabled list with a hamstring injury. Wright hurt himself running out an infield hit Friday night and is expected to miss 3 to 5 weeks.
''It's disappointing,'' he said. ''I kind of came to the realization that I wasn't going to be able to play today and probably not the next day. I will hopefully get this thing healthy as quickly as I can and get back on the field.''
Kelvin Herrera (4-5) earned the win with three innings of relief in which he walked one and struck out three without giving up a hit.
''I was able to throw breaking balls for strikes, and my changeup was really good,'' he said. ''I pitched 3 1-3 (innings) in the minors earlier this year, but this was my longest outing here. You have to be ready to pitch whenever you're asked.''
Greg Holland got the final three outs in the 12th for his 29th save in 31 chances and 22nd straight.
Aardsma (2-1), filling in while closer Bobby Parnell is sidelined with a sore neck, blew the save in the ninth inning Friday night before the Mets came back to win on Eric Young Jr.'s homer.
''Role has nothing to do with that,'' Aardsma said. ''It's my pitches. It's attacking first pitch. Up here I'm not thinking of anything about any role, I'm just trying to execute my pitches, and I didn't do that.''
The Mets, 9-3 in interleague play, provided the comeback Saturday by scoring two runs in the eighth on Josh Satin's two-run single against Aaron Crow.
Bruce Chen put the Royals in position to win, pitching six strong innings. He gave up four hits, struck out eight and didn't walk anyone in his fourth start of the season - all since July 12 - to lower his ERA to 2.03. He is 1-0 with three no-decisions as a starter and has gone exactly six innings in each outing.
Chen even singled and scored a run in the Royals' three-run third.
''That three-run inning ended up being really huge for us, and I was glad to be a part of it,'' Chen said. ''It felt really weird running the bases, I haven't done that in a long time.''
Chen's only blemish was Daniel Murphy's home run leading off the second inning.
George Kottaras got that run back to start the Royals' three-run third by homering off Jeremy Hefner, who was originally scheduled to pitch Sunday. Because of bullpen injuries, the Mets are going back to a five-man rotation until Jonathon Niese returns from a shoulder injury.
Hefner also worked six innings, allowing three runs, eight hits - including the 20th homer of the season. He walked no one and struck out six.
Hefner is 0-3 with two no-decisions in his past five starts. He gave up a total of 21 runs in his previous three outings.
After Murphy gave the Mets a 1-0 lead in the second with his ninth homer, the Royals came right back to grab the lead.
Kottaras' fifth homer just eluded leaping Marlon Byrd in right field. Chen, Lorenzo Cain and Eric Hosmer followed with singles to load the bases, bringing up usual designated hitter Billy Butler, who made a rare start at first base.
Hefner struck out Butler, but Alex Gordon gave the Royals their first lead of the series with a sacrifice fly to deep right. Miguel Tejada added an RBI single, the second of his three hits.
NOTES: The Mets recalled OF Mike Baxter from Triple-A Las Vegas to replace Wright on the roster. He flied out as a pinch-hitter in the 10th. ... Hosmer moved from first base for Butler and started in right field for the first time this season. Butler made his seventh start at first. Hosmer replaced him in the seventh. ... Hefner is 0 for 30 batting this season. He was 2 for 20 last season with a home run.