NEW YORK -- The New York Mets pushed right-hander Noah Syndergaard back a day in the rotation in hopes of giving him some extra rest following the longest outing of his career last week. But the Mets might need to push Syndergaard again Wednesday in the finale of a two-game series against the Kansas City Royals at Citi Field.

The Mets won the opener of the 2015 World Series rematch 2-1 on Tuesday, when they needed five relievers to throw the final 8 2/3 innings after right-hander Bartolo Colon was hit on the thumb by a line drive off the bat of Royals leadoff hitter Whit Merrifield.

"We might have been out of pitchers (Wednesday) if we got much deeper," Mets manager Terry Collins said afterward.

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The Mets are likely to be without right-handers Hansel Robles and Erik Goeddel, who threw 3 2/3 innings and two innings, respectively, as the first two pitchers out of the bullpen Tuesday. Left-hander Sean Gilmartin, who was promoted from Triple-A Las Vegas on Tuesday afternoon, may also be unavailable since he threw 100 pitches in a start for Las Vegas on Sunday.

Fortunately for the Mets, Syndergaard has developed into a workhorse in his first full major league season. The long-haired 23-year-old has pitched into the seventh inning in eight of his 13 starts.

Syndergaard threw a career-high 8 1/3 innings in his most recent start June 14, when he allowed two runs (one earned) on five hits and no walks while striking out 11. He threw 115 pitches, one shy of his career high.

The Mets originally had Syndergaard scheduled to start the series opener Tuesday but decided to push him back in order to get him some rest and to set him up to pitch the opener of a series against the National League East-leading Washington Nationals next Monday.

Had Syndergaard pitched Tuesday, he would have pitched again Sunday against the NL-worst Atlanta Braves.

"Thought we'd give him some extra time," Collins said before Tuesday's game. "We can move Noah back a day, give him an extra day with all the pitchers he threw. That will allow him to pitch in Washington also."

The Royals on Wednesday counter with left-hander Danny Duffy, who will be making his seventh start since joining the rotation May 15. Duffy is 2-1 with a 3.25 ERA since replacing right-hander Kris Medlen, who was 1-3 with a 7.77 ERA before suffering a strained rotator cuff.

"Danny's come in and helped fill that hole," Royals manager Ned Yost said Tuesday. "He's done a great job."

The matinee Wednesday will be the last of the four games this year between the Royals and Mets, who split a season-opening two-game series in Kansas City in April. This is the 11th time since interleague play began in 1997 that the previous season's World Series teams have played in the regular season the following year.

It is also the third time a reigning champion has played in the stadium in which it won the title the previous year. The New York Yankees traveled to face the Mets in 2001 after winning the decisive fifth game of the 2000 World Series while the Boston Red Sox visited the St. Louis Cardinals in 2005 after completing a four-game sweep of the 2004 World Series at Busch Stadium.