WASHINGTON -- Before the series finale against the Mets, manager Dave Martinez lauded Patrick Corbin for his ability, at times, to keep the Nationals in games.

That proved to be the case early on Wednesday, as Corbin walked off the mound after the fourth inning having faced one batter above the minimum and with his team facing only a 1-0 deficit.

The Mets, though, added a second run in the fifth and things unraveled for Corbin and the Nationals from there in an eventual 9-1 defeat.

In the sixth, Corbin allowed back-to-back homers to Luis Torrens (his second of the day) and Francisco Lindor. A double from Pete Alonso and a hard-hit single from J.D. Martinez followed, and Corbin’s start came to an abrupt end. Both runners later scored as part of a six-run Mets sixth.

“Couple of heaters on the corner, but elevated,” Corbin said of where the game got away from him.

“Not the best sinker today, they put some good swings on some of those pitches. Pitch count was fairly low through those first five innings. That sixth inning, they kind of opened that gap and separated the game a little bit.”

Corbin tossed 5 1/3 innings, allowing seven hits and six earned runs with three strikeouts and one walk. The veteran is now 1-7 on the year with a 6.15 ERA -- the second-worst mark among qualified MLB starters.

“Patrick threw four balls that were left up and paid the price for them,” said Martinez.

In the final season of a six-year, $140 million pact he signed before the 2019 campaign, Corbin has remained a fixture in the Nationals’ rotation. Despite his ability to eat innings and keep some games competitive, the results ultimately haven’t been there. Other starters, meanwhile, are vying for opportunities.

“We’re not quite there yet,” Martinez said when asked if a decision could be coming on Corbin’s future in the rotation.

“Look, he’s been keeping us in games. He’s the one guy we can count on when things go awry; he’s going to get us into the sixth inning and give our bullpen a break. He pitches good enough and we don’t give him any runs. We’ve got to give him some run support and he’ll be fine. But we’ll see what happens in the next few weeks. We’re not quite there.”

With rookie Mitchell Parker pitching well in the rotation and 23-year-old DJ Herz (the club’s No. 12 prospect per MLB Pipeline) making his Major League debut on Tuesday, the Nationals may choose to keep the lefties in the mix.

Opening Day starter Josiah Gray, meanwhile, is continuing to work his way back from injury, with a rehab start expected Sunday at Single-A Fredericksburg. Righty Cade Cavalli (No. 5 prospect) has made multiple rehab starts as he nears a return from Tommy John surgery. Even with Trevor Williams on the 15-day injured list (right flexor muscle strain), there will potentially be more readily available starters than spots in the rotation.

“Typically, all that stuff works itself out,” Martinez said.

As much as Corbin has struggled for consistent results, he’s also been hurt by a lack of run support. The lefty ranks last in the National League in overall run support this season and the Nationals’ offense was again held in check Wednesday by Mets starter Luis Severino.

Severino threw eight innings of one-run ball across an efficient 92 pitches. The Nationals didn’t have a runner in scoring position until the eighth inning.

“He’s an amazing pitcher,” said Nationals first baseman and Severino’s former Yankees teammate Joey Gallo. “When he’s healthy, he’s one of the best in the game and he showed that today, for sure. So, I think we could have been better for sure, but you tip your cap when he’s pitching that well.”

The Nationals dropped the first three games of a seven-game homestand and have now lost five of their last six overall.

“It was a rough series, but we can’t feel sorry for ourselves,” Martinez said. “We fell behind in all three of these games. It’s tough to play from behind.

“We’ve got to start to get things going. We’ve got to relax. We get guys on base, and all of a sudden, guys are trying to hit home runs. They’ve got to stay with the plan -- try to hit the ball in the gap and start scoring some runs early.”