So far this year, the Mets’ rotation had been Matt Harvey, Jon Niese and not much else. But heretofore-struggling Dillon Gee soothed those worries and shook off his own woes, pitching the Mets to a 2-0 shutout of the Nationals yesterday and a series win over one of the best teams in baseball.

Gee (1-3) scattered three hits in 5 1/3 shutout innings, smothering Washington before 26,225 at Citi Field. It was an auspicious bounceback start for the back end of the rotation, and Gee in particular, who earned his first win since returning to the mound from surgery to replace a damaged artery in his right shoulder.

“It’s huge,” Gee said. “We know, it’s no secret. We know we’ve got to step up the back end, and we haven’t been doing how we’d like. That’s the truth. We’ve got to step it up, and I’m just glad I was able to do my part. It’s been really eating away at me the past few weeks, not doing my job, so it feels good.’’

Harvey and Niese are 7-1, but the rest of the rotation had been 1-7 with a 6.87 ERA, including Gee’s 8.36. He had been forced to stew since being shelled for five earned runs in just 4 2/3 innings at Colorado.

“I needed to step it up. I knew I had to turn it around and do my job,’’ said Gee. “It was definitely in the back of my mind that I hadn’t been getting it done and something had to change.’’