Don’t look now, but the Mets are a win Tuesday away from matching the best start in franchise history -- established by the 1985 edition, which opened 5-0.

“Everybody is excited about the start,” Terry Collins said after the Mets beat the Washington Nationals, 4-3, Monday night at Citi Field on Daniel Murphy’s walk-off RBI single. “We talked about it in the first meeting we had in spring training -- the importance of getting out of the gate. No. 1, we know it’s a long year. We know it’s four games. But I think we want to show our fans, what we say, maybe there’s some truth to it. And that is that we’re a better team than people are giving us credit for.”

Murphy had two key plays in the final frame -- the hitting heroics with the single off Henry Rodriguez and a fielding play that preceded it.

In the top half while manning second base, Murphy ranged to his right and smothered Ryan Zimmerman’s grounder up the middle. He then got the ball to Ruben Tejada covering the bag for a forceout of Ian Desmond that ended Jon Rauch’s second scoreless inning.

“A great play to knock that ball down,” Collins said. “If that balls gets through, they’re first and third. Holes open up in the infield. Dan Murphy, what can I say? Every minute of every game he’s all out.”

Murphy came to bat in the ninth with Mike Baxter at third base, Tejada at second and none out.

Baxter, pinch-hitting, had walked to open the bottom of the ninth. Tejada then produced a sacrifice bunt with two strikes, which Rodriguez fired past first base. On the play, Baxter nearly tried to score. But third base coach Tim Teufel managed to hold Baxter up halfway down the line. Baxter slid awkwardly while stopping. Murphy then followed with the game-winning single.

“The last thing I wanted to do was have the first out at home,” Teufel said. “So when I saw him reach down for the ball, that’s when I decided to put the brakes on for him.”

Said Baxter: “A skid out. I took some grass, but it worked out well. Thankfully I saw the stop sign and pulled up. It all worked. I was trying to score. Once I saw the ball get away I figured we might have a chance to score. And then he put the brakes on. I did my best to stop, but I lost the edge. I just saw the replay. It’s not too nice.”

As for bunting with two strikes on a challenging slider from Rodriguez, Tejada said: “It’s a tough at-bat, but I have to do my work in that situation. A runner at first, nobody out, I have to put the ball in play. It’s not easy.”

• As for Mike Pelfrey’s performance in allowing three runs in 5 2/3 innings, Collins said: “I said, ‘Look, you’ve got to be positive. You got groundballs.’ It’s there. Stay with it. … I thought Mike battled. I thought he really did. I thought he hung in there. That’s what he does. He did it last year. I can see him doing it this year. That’s why he gives you 200 innings.”

Said Pelfrey: “I think we introduced the curveball maybe in the fourth or fifth inning. That kind of helped. Definitely, early, I missed a lot of pitches over the middle of the plate. You can’t do that. I think I need to be down a little bit more and, like I said, keep it out of the middle and I think I’ll be fine. But stuff-wise, I thought it was good. If I could take that out there every night, it’s going to be a good year.”