NEW YORK -- It just keeps happening. These Royals just hang around and hang around and wait for one key mistake. Then they pounce.
For the seventh time this postseason, the Royals came from behind to win. Fueled again by a patient offensive approach and a devastating defensive mistake -- this one by Mets second baseman Daniel Murphy -- Kansas City grabbed a 5-3 win in Game 4 of the World Series on Saturday night at Citi Field.
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The Royals, up 3-1 in the Series, are one win away from their first World Series championship since 1985. Game 5 is set for Sunday at 8 p.m. ET on FOX.
Murphy may be the most significant reason the Mets won the National League pennant, willing them to victory after victory in postseason play. But his eighth-inning fielding error on a routine grounder by Eric Hosmer allowed Ben Zobrist to scoot home with the tying run. Moments later, Mike Moustakas singled in the go-ahead run past the glove of a diving Murphy, and Salvador Perez knocked in another insurance run.
Then Royals manager Ned Yost called for closer Wade Davis to come in and get six outs, which he did. Checkmate. Davis had the Royals' first two-inning save in postseason play since Dan Quisenberry in Game 4 of the 1980 World Series.
"We feel like if we can keep the game close, we're going to find a way to win it," Yost said. "Our bullpen is so dynamic, they give us a chance to win those type of games. And it's a team that just looks for a little crack. If we find a little crack, they're going to make something happen."
Teams holding a 3-1 lead in best-of-seven postseason series are 68-12 (.850) all-time, and 39-6 (.867) in World Series play. No team has come back from a 3-1 deficit in the World Series since the Royals in 1985.
"When you win the first two games at home, going into it your goal coming in here is winning two games here," Yost said of having a chance to clinch on Sunday in New York, before the Series would go back to Kansas City. "But you know if you win one here, you've got two games at home, where we're really, really tough."
Trailing, 3-2, entering the eighth inning, the Royals drew consecutive one-out walks against Tyler Clippard, prompting Mets manager Terry Collins to call on closer Jeurys Familia to try for a five-out save. The first man he faced, Hosmer, sent a bouncing ball to the right side, where it scooted under Murphy's glove and into right field. As the largest Mets crowd in Citi Field history (44,815) grew mostly silent, Zobrist raced home.
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"I tried to one-hand it," Murphy said. "It probably deserved to be two-handed. I just misplayed it. It went right under my glove. They made us pay for it. It put us in a really bad spot, and that's frustrating."
The result was the second blown save of the Series for Familia, who also served up a game-tying homer to Alex Gordon in the ninth inning of Game 1.
"They truly don't ever stop," Collins said of the Royals' offense. "They have a very good lineup from top to bottom. They can do a lot of things. They're athletic. So like I say, you've got to make pitches and you've got to get outs when you have the opportunity."
Familia's misstep undid the early work of Mets rookies Michael Conforto and Steven Matz. The former became the third-youngest player to homer twice in a World Series game, while the latter delivered five-plus innings of two-run ball had New York poised to tie the Series.
Right-hander Chris Young started for the Royals and gave up two runs through four innings, then Danny Duffy, Luke Hochevar and Ryan Madson (1-0) bridged the gap to Davis.
"We can smell it now," Young said. "But we know we have work to do yet."

MOMENTS THAT MATTERED
It's an eighth thumpin': All postseason, the Royals have emphasized the keep-the-line-moving offensive approach. It worked with big rallies against the Astros in the American League Division Series and against the Blue Jays in the AL Championship Series. And starting with Murphy's eight-inning error, it was back again in Game 4 of the Fall Classic.
"The most important thing is they put the ball in play," Yost said. "They make things happen by putting the ball in play, and it's just a phenomenal group."
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Confor-two: Rookie? No problem. Left-on-left matchup? All good. Conforto bashed his second home run of the game off Duffy to lead off the fifth inning, making him the first rookie to hit multiple homers in a World Series game since Andruw Jones in 1996. Conforto's first homer led off the third inning against Young, giving the Mets a 1-0 lead.
"It's humbling and it's exciting," Conforto said. "I'll definitely remember those moments, the feelings I got on those two home runs is indescribable. You dream about those moments."
• Conforto mashes pair of homers

Big Bart's big out: Things grew hairy for the Mets when Zobrist tied a Major League record with his eighth double of the postseason to lead off the sixth. Cain drove him home to chase Matz, and stole second against Jon Niese. Niese got two outs and handed the ball of to Bartolo Colon, and Cain went back to work. The Royals' speedster moved to third on the Colon's throwing error on a pickoff attempt. But the 42-year-old pitcher wasn't going to let that be his legacy; he fanned Perez on a slider to end a 10-pitch at-bat, preserving the Mets' 3-2 lead.
• Niese, Colon combine for three huge outs

How many outs are there? The Royals gave the Mets an uncontested run in their two-run third inning. With Wilmer Flores on third base and one out in a 1-1 game, Curtis Granderson sent a fly ball to medium-to-short right field, where Alex Rios made an easy catch and momentarily relaxed, clearly thinking it was the final out of the inning. He quickly saw Flores sprint home from third base and made a desperation throw home, but it was too late. Kansas City believed Flores tagged early and challenged, but the call was allowed to stand and New York had a 2-1 lead.
• Rios' gaffe opens door for Mets

QUOTABLE
"What they did tonight is what they've been doing the whole playoffs. It's a group of guys that have the utmost confidence in themselves. I don't think at any point these guys thought that they were going to lose." -- Yost, on the Royals' determination
"That's not the reason we lost this game. That's definitely not the reason we lost this game." -- Mets third baseman David Wright, on Murphy's error
WHAT'S NEXT
Royals: Right-hander Edinson Volquez will take the mound for Kansas City in Game 5. Volquez just returned to the Royals on Saturday from the Dominican Republic, where he spent the past few days with family following the death of his father. Volquez pitched six innings of three-run ball in Game 1 without the knowledge that his father had died just hours before the game.
Mets: Now at 208 innings and counting, right-hander Matt Harvey will look to extend New York's season in Game 5 on Sunday. Though there is a chance Harvey could appear in relief in a potential Game 7, this will most likely be his last appearance in his first year back from Tommy John surgery. Harvey is 2-0 with a 3.38 ERA in three postseason starts, including a quality start in Game 1 of the World Series.