SAN DIEGO -- The Washington Nationals' Matt Grace was anxious for his Southern California family to see him pitch on Friday against the San Diego Padres. They just didn't expect him to be starting in place of Max Scherzer.

"They probably heard it from you guys before they heard from me,'' Grace told the media.

Grace, a last-minute substitute, threw 4 1/3 scoreless innings and helped the Nationals beat the Padres 7-1.

"Gracie saved my bullpen where I could just go one inning or a fraction of an inning,'' Washington manager Dusty Baker said.

Howie Kendrick christened the game with his seventh homer of this season, giving Washington a lead it never relinquished.

Grace, a former UCLA standout, was a late replacement for the injured Scherzer. The Nationals ace was waylaid by a sore neck and was placed on the disabled list before the game.

That left Grace to make his first start in the majors in his 61st appearance. His last start came in 2012, when he was pitching for Class A Potomac.

But Grace, a left-hander with a fastball-sinker mix, was tough against the Padres. He surrendered two hits and a walk with a strikeout in 52 pitches.

"He threw the ball great,'' Scherzer said. "For him to go out there and give us 4 1/3 innings, that was exactly what we needed.''

Joe Blanton (2-2), who pitched a scoreless sixth, got the win. Four other Washington pitchers combined to four-hit the Padres, with Sammy Solis getting the final three outs.

"They did a great job,'' Baker said. "Things just sort of worked out. We liked the matchups that we had, especially after Gracie."

Luis Perdomo (6-8) lost for the third time in his last four starts. He worked six-plus innings and allowed five runs (three earned), six hits and three walks with five strikeouts.

"I felt really good,'' Perdomo said through a translator. "Obviously the results didn't end up the way we wanted.''

The Nationals scored twice in the seventh inning on pinch-hitter Alejandro De Aza's sacrifice fly and Kendrick's RBI single for a 5-1 cushion to end Perdomo's night.

Adam Lind's run-scoring single in the sixth scored Anthony Rendon for a 3-1 edge.

Dusty Coleman's 415-foot solo shot in the fifth, which landed in the second deck, pulled the Padres within 2-1.

Grace was in a jam in the second after a leadoff single by Carlos Asuaje and a walk to Jose Pirela. But Grace got a double-play grounder from Yangervis Solarte and Wil Myers to fly out.

"There was no room to throw more pitches than I should have,'' Grace said. "I tried to attack and be locked in early as early as possible to try and extend my outing a little bit.''

Washington forged ahead 2-0 in the second when San Diego got sloppy. Coleman's errant throw from shortstop on a force at second allowed Matt Wieters to come around and score.

Kendrick started the game with a homer for the sixth time this season as the Nationals took a 1-0 lead. He redirected Perdomo's 83 mph slider over the left-center field fence.

"Honestly he wasn't bad at all,'' Padres manager Andy Green said of Perdomo. "He hangs the slider to Kendrick to start the game off, he doesn't want to do that. From that pitch on all the way up until kind of the last inning he threw, I thought he was really good.''

NOTES: Nationals manager Dusty Baker said RHP Stephen Strasburg will be activated off the disabled list and start Saturday. ... Nationals 1B Adam Lind was the lineup over Ryan Zimmerman, although Zimmerman entered in the seventh inning. ... Padres RF Hunter Renfroe was out of the lineup. Renfroe is scuffling, with his last home run coming July 25.