Delgado said he felt sore after the triple and that he planned to see a doctor on Tuesday. He thought the injury was relatively minor.
"I don't see it as a DL," Delgado said. "We'll see how it feels in the morning, then we'll have an appointment and then we'll take it from there."
Delgado said he could have played if needed Monday night.
"When I went in the cage and started getting loose, it was a little sore. I figured I'd try to take care of it now," he said.
Fernando Tatis started at first base in his place and had a hit and a walk.
Gary Sheffield was inserted into the lineup as the left fielder and cleanup hitter and had an RBI single. He also dropped Emilio Bonifacio's easy fly ball leading off the game for a two-base error, the fifth by the Mets' outfielders this year.
It was just the sixth start in 19 games for Sheffield, who signed with the Mets on the eve of the season after Detroit released him.
"I was looking for a little more pop in the lineup," Mets manager Jerry Manuel said. "We're getting a lot of hits, but not extra-base hits."
Sheffield is batting .154 with a double and a home run. Ryan Church started in right and had a hit and a sacrifice fly.
New York hit just six home runs in its first 10 games at Citi Field -- none between the power alleys. Manuel doesn't believe batters are become psyched out by the big dimensions.
"I don't think so because opposition hit the ball, you know?" he said before referring to Austin Kearns' fifth-inning drive for Washington on Sunday that landed on the painted black turf that serves as the batters' eye.
"They put one out to center field, so everybody's going to say, 'Dang, we're out there to do that,'" Manuel said.
David Wright, who led the NL with 23 strikeouts, had a new look. Between Sunday's and Monday's games, he shaved his hair into a crewcut, as he did in May 2007.
"It's low maintenance. It's hot outside," he said. "Hopefully, it has some wins in it."
Manuel also said that left-hander Oliver Perez, 1-2 with a 9.31 ERA, will take his next scheduled turn in the rotation, on Saturday at Philadelphia. Manuel thinks Perez's issues are related to mechanics and that he'll be helped by facing the Phillies. Perez was 1-0 with an 0.35 ERA against Philadelphia in four starts and 26 innings last year.
"I have to watch, evaluate and see what happens after that," Manuel said. "He's pitched well against them, and I'd like to see what he does."