WHAT IT MEANS: R.A. Dickey’s pursuit of 20 wins got a little more challenging. Dickey surrendered a game-tying solo homer to Tyler Colvin in the fifth on an 0-2 knuckleball and settled for a no-decision to remain at 15 wins.

The Mets ultimately lost to the lowly Rockies, 3-1, Monday night before an announced crowd of 23,833 at Citi Field. The Amazin's again dropped to a season-worst eight games under .500. With its victory, Philadelphia has caught the Mets for a third-place tie in the division.

In a tie ballgame in the eighth, Josh Edgin errantly shoveled the ball to first base on Jonathan Herrera’s bunt, sending it into foul territory down the line and allowing Herrera to advance to second base for a single and error. After Herrera was bunted to third, Kelly Shoppach -- who had entered as a pinch hitter for Josh Thole the previous half-inning -- committed his first passed ball as a Met. Herrera scored the go-ahead run.

A half-inning later, the Mets loaded the bases with two out, and right-hander Matt Belisle entered to face Scott Hairston. Terry Collins countered by using lefty-hitting Jordany Valdespin as a pinch hitter. Valdespin sent a grounder to first base, and was beaten to the bag by the slimmest of margins after sliding headfirst. Valdespin got in first-base ump Adrian Johnson's face after the inning-ending call, but replays suggested the ruling appeared correct. Valdespin dropped to 9-for-his-last-56 (.161). It was Johnson's incorrect foul call on Carlos Beltran's shot down the third-base line allowed Johan Santana's no-hitter to materialize.

Jon Rauch surrendered a run in the ninth -- only his second in his past 22 appearances -- to give Colorado a two-run cushion.

The Mets had staked Dickey to a 1-0 lead in the first when David Wright, who had doubled, scored on Daniel Murphy’s single against Rockies starter Alex White. But the Mets offered no other support and Dickey departed for pinch hitter Justin Turner in the seventh with the score tied.

Dickey’s line: 7 IP, 3 H, 1 R, 1 ER, 2 BB, 6 K.

Dickey gets his next crack at win No. 16 Saturday when he faces the Houston Astros. He is staying on an every-five-games schedule as the lone starting pitcher exempted from the six-man rotation.

“I think it gave him two more starts at the end of the season,” Terry Collins said regarding Dickey pitching every fifth game rather than every sixth like his fellow starting pitchers. “It’s basically designed for, ‘Hey look, this guy has earned the right to achieve anything he can at the end of the season.’ He’s earned that. He’s earned that respect. And I hope he wins his next four starts, or five starts. Because I think if he does, and at the end of the year he’s got 22 wins -- he’s 22-4 -- those are pretty good numbers.

“The thing we’re going to be careful of is if it gets toward the last couple of weeks and we think that he’s getting pretty fatigued himself -- because we want him back, too -- we’ll look at giving him some extra time.”

WEB GEMS: The Mets had a series of highlight-reel fielding plays in the middle innings. Wright handled Wilin Rosario’s absolute smash to third base in the fifth. After Colvin’s solo homer evened the score at 1, Ruben Tejada then made a tough barehanded play on D.J. LeMahieu’s grounder and threw to first base in time. An inning later, Mike Baxter made a sliding catch in shallow right field to snare Guillermo Moscoso’s flare.

WHAT’S NEXT: Chris Young (3-6, 4.50 ERA) opposes Rockies right-hander Jhoulys Chacin (0-3, 7.30) in Tuesday’s 7:10 p.m. game.