WASHINGTON — Jose Butto was largely an afterthought when the Mets looked to fill rotation openings this season, but Wednesday night he provided a glimpse of his potential.

The right-hander pitched strong into the seventh inning, receiving a no-decision in the Mets’ 3-2 loss to the Nationals.

Butto, who was recalled from Triple-A Syracuse on Friday when rosters expanded, allowed two earned runs on six hits and one walk, with six strikeouts, over 6 ¹/₃ innings.

Butto took a shutout into the seventh, but was removed after allowing two singles (both runners later scored).

“He stayed in attack mode,” manager Buck Showalter said, noting that the outing was Butto’s longest of the season. “That was as much as you could expect him to do. It was good to see, especially this time of year when you know he’s been pitching a lot, to have him make that type of contribution.”

Jacob Young’s RBI single in the ninth inning against Phil Bickford gave the Nationals the win and a split in the two-game series.

The Mets are 1 ½ games ahead of Washington in their bid to avoid the NL East basement.

Butto’s performance was the best of his six career major league appearances, four of which have come as a starter.

With Syracuse this season the 25-year-old started 19 times and pitched to a 5.93 ERA.

That underwhelming work explains why David Peterson and Tylor Megill, despite their own troubles this year, received chances in the Mets’ rotation throughout the season while Butto remained in the minors.

Butto cited the usage of the automated strike zone at Triple-A as a factor in his struggles.

“Syracuse was different — everybody knows the ABS is a challenge,” Butto said. “This year was a little bit slow for me as compared to other years in the minors.”

Butto started two games for the Mets in April, then had one relief appearance for the team in May and another in August.

The Mets needed a starter on Wednesday after Carlos Carrasco was removed from the rotation last week, then broke his right pinkie Sunday when a 50-pound dumbbell fell on the finger during a workout.

Showalter was non-committal about whether Butto would receive another start.

Before the game, the manager mentioned Joey Lucchesi and Denyi Reyes as other rotation possibilities.

“We have options — it depends on what everybody wants to look at between now and the end of the year,” Showalter said. “There’s a lot of ways you can go. You kind of look at next spring what’s going on as far as options and not options … it’s important to look at guys in different roles, too. Whether it’s Butto as a reliever or Lucchesi, I’m not sure exactly what will end up happening, but there is a lot of talk about it.”

Francisco Lindor delivered an RBI single in the first inning to give the Mets a 1-0 lead.

Brandon Nimmo opened the game with a double before Lindor brought him home, then stole second.

The stolen base was Lindor’s 26th this season, equaling his home-run total and giving the Mets shortstop an opportunity to join the 30/30 club in homers and steals.

Mark Vientos’ RBI single in the fifth extended the Mets’ lead to 2-0. Lindor doubled leading off the inning, and after Pete Alonso was intentionally walked for the second time in the game, Vientos delivered the two-out hit.

Butto allowed a leadoff single to Dominic Smith in the second, but got Carter Kieboom to hit into a double play and struck out Jake Alu.

Smith singled with two outs in the fourth, but Butto rebounded to strike out Kieboom. Butto allowed a two-out double to Young in the fifth before getting CJ Abrams to ground out.

Butto was allowed to continue into the seventh at 74 pitches, but was removed after he allowed his second single of the inning, to Alu, which put runners on the corners with one out. Ildemaro Vargas brought in a run with a single against Trevor Gott.

The Nationals tied it 2-2 on Abrams’ single under the glove of a sliding Ronny Mauricio.