WASHINGTON — Cincinnati’s offense finally woke up, rallying twice to help the Reds end their road trip in satisfying fashion.

Drew Stubbs hit a two-out single in the 10th inning, driving in Jay Bruce and helping the Reds to a 5-4 victory over the Washington Nationals on Sunday.

“It’s always easier to do something again when you’ve already done it,” said Jonny Gomes, who tied the game in the ninth with a pinch-hit double. “We’ve come from behind and won some games in our last at-bat. We know we have that ability, and I think you saw today this team’s got a real deep bench and a real deep bullpen.”

Bruce ignited the decisive rally with a single to left off Doug Slaten (2-1). After Laynce Nix singled, Miguel Batista replaced Slaten and Stubbs shot another single to right, his third hit of the game.

“His batting average isn’t where he’d like it to be,” Reds manager Dusty Baker said of Stubbs, who is hitting .241. “But he’s come through with a lot of clutch hits for us.”

Pinch hitter Scott Rolen had given the Reds a 4-2 lead in the ninth with a two-run homer off Matt Capps, one batter after Capps allowed Gomes’ tying pinch-hit double.

“There’s no ifs, ands or buts about it,” said Capps, who has blown three saves in four chances after converting his first 16. “I missed a lot of pitches. That one’s on me.”

Washington manager Jim Riggleman lamented Capps’ ineffective slider, a go-to pitch earlier in the season. Riggleman thought Capps had Rolen struck out on a checked swing only to have first-base umpire Paul Schrieber rule that Rolen didn’t go around.

“If it can go wrong for (Capps) right now, it’s going wrong,” Riggleman said. “We’re not making plays when he’s out there.”

With the Reds down 2-1 in the ninth, Capps entered and Stubbs doubled over the head of Roger Bernadina in right before Gomes ripped Capps’ first pitch down the left-field line for a 2-2 tie. Rolen then clubbed a hanging 2-2 slider into the left-field stands, his 14th of the year.

Washington tied the game against Francisco Cordero in the bottom of the inning on pinch hitter Michael Morse’s two-run double to right-center. Cordero (2-3) picked up the win despite blowing his fourth save in 20 tries.

Nick Masset got the final three outs for his first save, wiggling out of a two-out, two-on jam by getting Ian Desmond to bounce to second.

The Reds improved to 5-1 in extra innings and won their second straight game.

“We’re going to keep it going,” Gomes said. “It’s good to carry a win into home.”

Orlando Cabrera led off the game with a double, moved to second on Miguel Cairo’s sacrifice bunt and scored when Joey Votto lined a single to right.

Washington tied it in the bottom of the inning when Cristian Guzman doubled, advanced on Nyjer Morgan’s sacrifice and came home when Ryan Zimmerman poked a hit to right field.

In the fourth, Bernadina drew a two-out walk from Reds starter Bronson Arroyo, and Desmond followed with a double off the wall in left just past the mistimed leap of Nix.

Washington starter Craig Stammen yielded a run on seven hits over 6 2-3 innings. He walked none, struck out one and has not won in nine starts.

Despite the strong 66-pitch effort, Stammen was optioned to Triple-A Syracuse after the game to clear a roster spot for top prospect Stephen Strasburg, who will be activated to make his major league debut Tuesday against Pittsburgh.

“Somebody’s got to go, and it’s Craig and I feel terrible about that, too,” Riggleman said. “One of the guys who has been leaving it all out there for you takes the hit on this.”

Arroyo went eight innings, allowing two runs on six hits. He walked one and struck out five.

NOTES: Rolen’s pinch homer was the second of his career. … Nationals C Ivan Rodriguez, on the DL with lower back tightness since May 24, and LHP Ross Detwiler, on the DL while recovering from hip surgery, will both report to Class-A Potomac for rehab assignments Monday. Rodriguez expects to be activated in time to catch the debut of RHP Stephen Strasburg on Tuesday. Detwiler threw a bullpen session at Nationals Park on Sunday and will need several minor league outings. … Reds RHP Homer Bailey, on the DL since May 24 with right shoulder inflammation, experienced no issues during a bullpen session Sunday in D.C. and will make a rehab start for Triple-A Louisville early in the week.