ST. LOUIS -- R.A. Dickey had more than enough to hold off the St. Louis Cardinals and become the first pitcher in the majors to reach 18 wins this season.

He didn't have his best stuff, but still managed to strengthen his case in the NL Cy Young Award race.

Dickey was backed by Ike Davis' three-run homer that powered the New York Mets to a 6-2 victory over the Cardinals on Wednesday.

The knuckleballer allowed two runs in 6 2/3 innings en route to his 18th win, the first Mets pitcher to reach the mark since Frank Viola (20-12) and Dwight Gooden (19-7) both did it in 1990. Dickey (18-4) gave up eight hits and struck out five to help New York salvage a win to close out the three-game series.

"It was a battle for me," Dickey said. "I didn't really have a great feel for [the knuckleball] early on. I threw a couple of more fastballs than I ordinarily would have.

"I'm pleased with the results, but obviously I have a little bit of work to do."

Dickey should have five more starts as he tries to become a 20-game winner, which would further bolster his Cy Young resume. Considering where Dickey was just a few years ago -- in the minors trying to refine his knuckleball -- Mets manager Terry Collins said it has been an incredible journey.

"The whole story of what he's had to go through to get where he is today is truly one of the great stories of sports," Collins said. "I'm thrilled. I hope he wins it [the Cy Young]. But if he doesn't, he's certainly had a storybook season."

For now, Dickey says he is focusing simply on getting win No. 19, but he can't help think about reaching 20, too.

"Obviously, I hope for that," Dickey said. "I hope to win beyond 20. As far as getting to that plateau, it would be really satisfying, I think."

Davis gave the Mets a 5-1 lead with his 26th homer, and Daniel Murphy went 3-for-4 to lift his average in day games to an NL-best .351 (65 for 185). Josh Thole and Andres Torres had RBI singles, and Lucas Duda drove in the Mets' other run with a bases-loaded walk.

The Mets did most of their damage off of Cardinals starter Adam Wainwright (13-12), who allowed five runs and eight hits in five innings.

"I'd say he wasn't as sharp as he would like to be," St. Louis manager Mike Matheny said. "His game revolves around establishing his fastball, and he just didn't have that tight fastball command today."

However, Wainwright delivered the Cardinals' first run when he led off the third inning with a home run against Dickey. It was Wainwright's first homer of the season and the sixth in his major league career.

Former first-round pick Shelby Miller was much more effective for the Cardinals. Making his Major League debut, Miller struck out four in two innings of scoreless relief, including fanning the side in the seventh.

After Wainwright's homer cut the Mets' advantage to 2-1, New York stretched its lead in the fifth on Davis' shot.

"The average isn't going to be there," said Davis, who is hitting just .224 this season. "I'm just trying to help the team, and when I hit a home run, that helps the team."

Mike Baxter led off the fifth with a single and went to third one out later on Murphy's single. They scored on Davis' drive over the right field fence.

Notes

• Kyle Lohse (14-2) will seek to match Ted Wilkes, who started 15-2 in 1944, for the best start to a season for a Cardinals pitcher when he faces the Milwaukee Brewers on Friday.
• Dickey's ERA of 2.64 is second in the NL to Cincinnati's Johnny Cueto (2.58).
• The crowd of 30,090 was the smallest of the season in St. Louis.
• The game ended on a 9-4-6 double play when Adron Chambers was called out for failing to retouch second base as he retreated to first on Yadier Molina's fly ball to right.