Joe Girardi believes the Philadelphia Phillies will go as far as their pitching will take them.

"If you don't pitch, you don't have a chance," according to the Philadelphia manager.

On Monday, the Phillies' offense was just as important. Andrew McCutchen hit a walk-off, three-run home run in the bottom of the ninth inning and Philadelphia came from behind for a clutch 6-5 win over the visiting Washington Nationals.

The Phillies will now look for their third consecutive victory when they host the Nationals in the second game of a four-game series on Tuesday.

"We lean on each other in this dugout," McCutchen said on a postgame interview on NBC Sports Philadelphia.

It was the eighth walk-off victory for the Phillies this season, their most through the first 99 games since compiling nine in 1983 when they advanced to the World Series.

"We've got to keep pace and we've got to make up some ground," Girardi said, referring to the National League East-leading New York Mets.

Five relievers -- Brandon Kintzler, Connor Brogdon, Jose Alvarado, Hector Neris and Archie Bradley -- combined to allow just one run in 5 1/3 innings after Spencer Howard gave up four runs in 3 2/3 innings.

The Phillies will send left-hander Matt Moore to the mound on Tuesday. Moore (0-2, 5.79 ERA) is 0-1 with a 2.70 ERA in four career games (three starts) against the Nationals. He threw a scoreless inning in a relief appearance at Washington on May 13.

Philadelphia's Jean Segura had two hits on Monday and extended his hitting streak to eight games. Rhys Hoskins added a three-run home run, increasing his RBI total to a team-high 62.

The reeling Nationals will hope to avoid a sixth straight loss.

Closer Brad Hand has suffered blown saves in consecutive games, including serving up the three-run homer to McCutchen. On Sunday at Baltimore, he gave up two ninth-inning runs to take a 5-4 defeat.

On Monday, the Nationals produced 10 hits and five runs, the run total the club's best during the five-game skid, but they needed more.

Josh Bell and Josh Harrison came through with consecutive triples in the fourth inning, the first time Washington accomplished the feat since 2005.

"Hitting's really weird," Washington manager Dave Martinez said. "As we all know, hitting comes and goes, it really does. But you can't force it. You've got to just let it happen."

The Nationals will turn to Erick Fedde to try to halt the losing streak. Fedde (4-7, 4.88 ERA) is 2-5 with a 5.77 ERA in 10 career outings (nine starts) against the Phillies, including 0-1 with a 8.00 in two starts this year.

In his latest outing, Fedde got a no-decision against the Miami Marlins on Wednesday after allowing one run, which was unearned, in six innings. He gave up four hits and a walk while striking out four in a game that Washington lost 3-1 in 10 innings.

"I think right now ... it feels like there's been guys on base constantly," Fedde said after the Wednesday game. "So I guess maybe it's just being effective with nobody on base early in the innings. And I don't know, I just -- being more aggressive with my off-speed early in the count and just getting more strikes."

Fedde's command has been an ongoing issue, as he has issued 16 walks in his past 27 2/3 innings, but the Nationals remain confident in him.

"We'll get him back on track," Martinez said.