CHICAGO -- The World Series is within reach for the New York Mets.

A 5-2 victory over the Chicago Cubs on Tuesday -- New York's first victory at Wrigley Field in five tries this season -- propelled the Mets to a three-games-to-none lead in the National League Championship Series.

Even so, the Mets aren't looking at anything beyond Wednesday's chance to clinch.

"You can't look past tomorrow," said third baseman David Wright, the Mets' captain. "You have to continue to put your foot on the gas and take advantage of the type of baseball that we're playing and the type of pitching that we're getting."

A Game 4 win would complete the first four-game postseason sweep in franchise history and give the Mets their first World Series trip since 2000 and fifth overall.

New York received another strong pitching performance, this one from right-hander Jacob deGrom, who got better as the game progressed.

The Mets also got timely hitting and caught a sixth-inning break as they pushed the Cubs to the brink of elimination.

In the third inning, Mets second baseman Daniel Murphy tied the all-time major league record by homering in a fifth consecutive postseason game.

New York then snapped a 2-2 tie in the sixth, scoring on a wild pitch on a third strike that could have ended the inning.

DeGrom improved to 3-0 in the postseason after a slow start. He pitched seven innings, allowing two runs on four hits and one walk while striking out seven.

"In the third inning, I said if we get five out of the guy tonight, we'll be lucky," Mets manager Terry Collins said. "He didn't have very good stuff early. ... Then all of a sudden in the fourth and fifth inning, he started making pitches."

New York right-hander Tyler Clippard pitched a scoreless eighth inning, and closer Jeurys Familia worked a 1-2-3 ninth for his third save of the series.

Right-hander Trevor Cahill, the third of seven Cubs pitchers, took the loss in front of an announced crowd of 42,231.

Mets center fielder Yoenis Cespedes stole third and scored with two outs in the sixth inning on what should have been an inning-ending third strike to left fielder Michael Conforto from Cahill.

The ball skipped past catcher Miguel Montero for a wild pitch as Cespedes sprinted home and Conforto reached base.

"That was our fault," Cubs manager Joe Maddon said. "We permitted him to (steal third). That was a very big play right there."

New York added two more in the seventh. Chicago left fielder Kyle Schwarber misjudged a Cespedes one-out fly ball that dropped for a single, scoring Wright.

Murphy, who reached on an infield single earlier in the inning, advanced to third on the throw and made it 5-2 when he came home on first baseman Lucas Duda's grounder to first.

Cespedes and Wright each had three hits, while Murphy went 2-for-5 with two runs. The Mets collected 11 hits to the Cubs' five.

"We've got a pretty good offensive club, especially in hitters' parks," Collins said. "We've shown that all year long. In places that people hit, we hit."

The Mets hit Cubs right-hander Kyle Hendricks for a first-inning run on Cespedes' two-out double to left-center.

Schwarber answered with a solo home run in the bottom of the inning, launching deGrom's 3-2 pitch to the left field bleachers for his fifth of the postseason and a 1-1 tie.

Murphy gave New York a 2-1 lead in the third with his two-out, solo homer to right-center. With the shot, his sixth of the playoffs, Murphy joined Carlos Beltran (2004 Houston Astros) as the only players in postseason history to homer five games in a row.

"I don't think I've seen anybody put on this kind of show on this stage like he has so far," Collins said.

The lead didn't last, though. In the fourth, Chicago right fielder Jorge Soler collected his third postseason homer, a solo blast to right-center that forged a 2-2 tie.

Hendricks, pulled for a pinch hitter after throwing four innings, wasn't involved in the decision. He gave up two runs on five hits, walked one and struck out four.

Maddon said his Cubs will regroup, be ready for Wednesday and hope to hand it back to their aces after a win.

"The big thing is to get back in the game," he said. "We win tomorrow's game and we can take it from there with (left-hander Jon) Lester and (right-hander Jake) Arrieta."

NOTES: Only one team rallied from an 0-2 deficit to win an NL Championship Series since the seven-game format was adopted. The 1985 St. Louis Cardinals came back to beat the Los Angeles Dodgers. ... The Mets were 0-7 during the regular season against the Cubs, including 0-4 at Wrigley Field. ... Chicago sends RHP Jason Hammel against New York LHP Steven Matz in Game 4 on Wednesday. Hammel had no decision in the Cubs' Game 4 win over the Cardinals in the NL Division Series last week. Matz took the loss as the Mets fell 3-1 to the Dodgers in Game 4 of the NLDS. ... Tuesday's game was the latest date for a game played at Wrigley Field. The previous latest, Oct. 15, 2003, came in the NLCS against the then-Florida Marlins. ... Cubs LF Kyle Schwarber's five postseason home runs are a franchise record for a rookie.