CINCINNATI — Bartolo Colon got an early start on New York’s trip to Cincinnati, and it paid off in a big way for the Mets.

Colon pitched six innings of five-hit ball and Matt Reynolds homered to the lead the Mets to a 5-0 victory over the Cincinnati Reds on Monday.

“We had a man on the mound today,” New York manager Terry Collins said. “Nothing fazes him. Gave us what he always does, quality innings. He’s an amazing guy.”

Colon (13-7) improved to 4-1 with a 2.25 ERA in his last seven starts. The Reds put a runner on third with nobody out on two occasions, and Colon wiggled out of the jam each time.

Kelly Johnson also went deep as the Mets won for the sixth time in eight games. It was New York’s 12th straight victory over Cincinnati.

The Mets remained one game back of St. Louis for the second NL wild card after the Cardinals won 12-6 at sliding Pittsburgh.

New York had a short turnaround after a 5-1 victory over Washington on Sunday night, arriving in Cincinnati early Monday morning. Four regulars — outfielders Curtis Granderson and Yoenis Cespedes and infielders Jose Reyes and Asdrubal Cabera — were out of the starting lineup.

But the 43-year-old Colon got plenty of rest after traveling to Cincy on Sunday.

“Never had any pressure at all. I knew a lot of the veterans were getting a day off today,” Colon said through a translator. “Getting ahead of the hitters was key for me.”

Jay Bruce went 0 for 4 with two strikeouts in his first game in Cincinnati since the Reds traded him to the Mets on Aug. 1.

“It was a bit odd, coming over to the visiting side for the first time,” Bruce said. “Definitely odd being on the other side, but once the first pitch is thrown, it’s just baseball.”

Robert Stephenson, one of Cincinnati’s top prospects, struck out nine in 5 1/3 innings. He allowed two runs and six hits, but fell short in his bid to become the first Cincinnati pitcher since Wayne Simpson in 1970 to win each of his first three major league starts.

The 23-year-old Stephenson (2-1), who beat Philadelphia and Colorado in a pair of spot starts in April, said feels less pressure in the majors than he did in the minor leagues.

“It’s just confidence,” he said. “I’m not trying to get back to this level. I’m already here. Now I’m just trying to have fun.”

Reynolds, recalled from Triple-A Las Vegas before the game, hit his third homer of the season with one out in the third inning. He also had an RBI single in New York’s three-run seventh and finished with three hits.

Reynolds checked into the Mets’ Cincinnati hotel at 9:15 Monday morning after flying all night from Salt Lake City.

“It’s everything I can ask for,” Reynolds said. “I just want to help the team win. It just happened I had a couple of big hits.”

Johnson led off the fifth with his 10th homer.

The Mets have hit 18 home runs in their last 11 games at Great American Ball Park and 185 overall this season for their best total since the 2006 team set the franchise record with 200.

GRACIOUS HOSTS

The Reds honored Bruce and his wife, Hannah, in a pregame ceremony for his contributions to the team on the field and the couple’s work in the community during his nearly nine seasons with Cincinnati.

AMBITIOUS

New York’s Wilmer Flores was thrown out by left fielder Adam Duvall trying to stretch hits in each of his first two at bats, at second in the first inning and at third in the fourth. Duvall is the first Cincinnati outfielder with two assists in one game since Bruce on Aug. 5, 2014, at Cleveland, according to the Reds.

DOUBLE TROUBLE

After tying their season high by hitting into four double plays in a 5-2 loss to St. Louis on Sunday, the Reds hit into double plays in each of the first two innings on Monday against the Mets.

TRAINER’S ROOM

Reds: 2B Brandon Phillips returned to the starting lineup after being scratched each of the previous two days with a sore left foot.

UP NEXT

Mets RHP Rafael Montero (0-0) and Reds LHP Brandon Finnegan (8-10) are scheduled to start on Tuesday. Finnegan has limited opposing batters to a .132 average (9 for 68) over his last three starts.