WASHINGTON -- A road trip that began with a pair of losses to a last-place team quickly turned into one of the Phillies' best stretches away from home in recent memory.

A balanced offensive attack helped the Phils (55-53) erase an early deficit against the Nationals (49-59) en route to a 9-5 win on Wednesday at Nationals Park. The victory not only clinched a winning record on this seven-game swing and set the club up for a potential four-game sweep on Thursday, but it also marked the first time that Philadelphia won four straight road games since July 24-28, 2015.

After falling two games below .500 with consecutive losses to the last-place Pirates to start the weekend, the Phillies have outscored their opponents 36-18 while firing off four straight wins. Bryce Harper had three hits and a pair of RBIs. Rhys Hoskins had a pair of extra-base hits, including a two-run homer. Didi Gregorius added a towering two-run homer to pad the lead in the seventh.

“We just struggled scoring runs there the first two days for whatever reason,” manager Joe Girardi said. “Sometimes it's unlucky, sometimes you don't see a guy well. But obviously, we've had big contributions from a lot of guys the last four days -- and it needs to continue.”

The latest outburst came after falling into a 3-0 hole on Wednesday. Chase Anderson allowed three solo homers in the first two innings, but he retired seven of the eight batters he faced after serving up the third homer -- and did not allow another hit outside of the three long balls.

Philadelphia responded with a four-run third inning that featured doubles by Andrew Knapp, Travis Jankowski, Jean Segura and Hoskins -- the last three of which drove in a run. The other run scored on an RBI single by Harper, who has reached base safely in all 14 games he's played against his former club this season. He's hitting .417 (20-for-48) with 10 extra-base hits, nine RBIs and a 1.374 OPS in those contests.

The unlikely hero on this night, however, may have been Matt Moore.

Making his first appearance since being moved to the bullpen for the second time this season, Moore was called on with Juan Soto stepping to the plate as the potential tying run with two outs in the bottom of the fifth. Moore not only retired Soto on a routine groundout, but he went on to pitch four innings for his first win of the season and came within one out of finishing the game.

“I loved the way he was throwing, and I just kept running him back out there,” Girardi said. “Wow, he was really, really good tonight. He picked us up big time. That's as good as I've seen him throw the ball here. He was a big reason we won tonight.”

It was a much-needed outing not just for the Phillies, but for Moore himself. The southpaw had not pitched since July 27, when he was tagged for six earned runs for a second straight start. With the addition of Kyle Gibson, Moore was removed from the starting rotation after posting a 10.80 ERA in his last two starts.

“Just in general, anytime you're contributing positively, you feel a little bit good about yourself, for sure,” Moore said. “Especially the last 11 innings that I had pitched for this club -- it was a detriment. So to be able to pull on that rope the same way everybody else was tonight feels good."

The Phillies will now hand the ball to Aaron Nola on Thursday with the hopes of securing a four-game sweep. Regardless of what happens in that contest, however, the Phils have guaranteed themselves a chance to play their way into first place by the end of the weekend.

They trail the first-place Mets -- whom Philadelphia will welcome to town for a three-game set beginning on Friday -- by 1 1/2 games.

“The last four games show what a good team we are,” Anderson said. “We've got to keep it up and continue to win series. We control our own destiny these next two months. It's going to be a fun ride and I look forward to going down the stretch with these guys.”