WASHINGTON — With the uncertainty surrounding Stephen Strasburg, there’s increased pressure on the Washington Nationals’ other starters, including veteran Gio Gonzalez.

On Sunday, he met the challenge.

Gonzalez pitched seven sharp innings, Anthony Rendon doubled home the tiebreaking run and the NL East-leading Nationals defeated the Philadelphia Phillies 3-2.

Gonzalez (11-9) gave up one run on four hits, striking out five with one walk.

“We talked the other day and I told him that he’s very important in this equation, especially with Stras out, and he responded,” manager Dusty Baker said.

Gonzalez rebounded from a rough outing against Atlanta in his last start when he allowed six runs in three innings and matched his longest outing of the season.

Since July 10, Gonzalez is 7-1 with a 3.51 ERA in 12 starts, a welcome development for Washington.

Washington turned three double plays, including in the eighth inning when the Phillies had runners on first and second with one out.

“As long as I can keep going deep in the game like that, I’ll take some groundball double plays and some groundballs to the middle infield anytime,” Gonzalez said. “These guys play great back there.”

It was 1-all when Bryce Harper drew a leadoff walk from starter Adam Morgan (2-10) to open the seventh. Rendon then doubled to the wall in left-center on 2-0 off reliever Edubray Ramos.

“I mean, 2-0 is a hitter’s count, so you’ve got to be aggressive in those situations and he just happened to leave the ball over the plate,” Rendon said.

Rendon later scored on a passed ball by catcher A.J. Ellis.

Mark Melancon pitched the ninth for his 41st save and 11th with Washington.

Tommy Joseph hit a tying homer for the Phillies in the seventh. Freddy Galvis homered in the eighth, but the Phillies left six runners on base.

“We need consistent at-bats rather than 15 to 20 to 25 home runs,” manager Pete Mackanin said. “Those are sexy stats, but getting a man in from third base with the infield back requires a groundball to short and that’s the type of thinking they need.”

The Nationals took the final three games of the four-game series.

Gonzalez had retired nine straight when Joseph connected for his 18th home run of the season.

“He was dealing. He had that changeup working,” Baker said. “He was ahead in the count most of the time with his fastball. It was well-located and he seemed like a guy on a mission.”

Morgan was looking to win back-to-back starts for the first time in his career. He allowed two runs on three hits over six innings plus one batter in his third straight solid effort and credited his recent success to mixing his pitches better.

“That’s the name of the game, changing speeds and keeping guys from cheating,” Morgan said. “I’m just going to keep throwing like I’ve been throwing.”

Washington took a 1-0 lead in the first. Trea Turner led off with a single and scored on Daniel Murphy’s major league-leading 42nd double.

REMEMBERING 9/11

Secretary of the Navy Ray Mabus threw out the ceremonial first pitch as part of the National’s 9/11 remembrance. The ceremony also included Midshipmen from the U.S. Naval Academy, first responders from the region, and service dogs and their owners. The Naval Academy Men’s and Women’s Glee Club & Gospel Choir performed the national anthem, which was concluded by a flyover.

WELCOME TO THE SHOW

Phillies OF prospect Roman Quinn, a second-round pick in 2011, made his major league debut and went 0 for 3 with a walk.

TRAINER’S ROOM

Phillies: 3B Maikel Franco (jammed right thumb), who pinch hit Saturday night, was out of the starting lineup for a fifth straight game.

UP NEXT

Phillies: RHP Jeremy Hellickson (10-9, 3.90 ERA) starts when the Phillies host the Pirates Monday in the first of four games. Hellickson is 0-2 with a 6.75 ERA in his last three starts. He’s 1-1 with a 4.50 ERA in two career starts versus the Pirates.

Nationals: Mat Latos (1-0, 7.71 ERA) makes his first start since being recalled by the Nationals. In his career, he’s 2-4 with a 3.11 ERA in 12 games against the Mets.