CINCINNATI -- Randy Keisler earned a win Tuesday night with his arm and his bat.
Keisler, who was called up from the minor leagues on Monday, had to bat against Luis Ayala with runners at second and third and one out because the Reds had run out of position players in the longest game of the season for both teams.
With the infield in, Keisler got a grounder past shortstop Jamey Carroll to drive in the game-winning run.
"I had nothing to lose," said Keisler, who made his first major-league appearance since May 25, 2003. "I'm a pitcher, but I've (batted) before. They know I'm a pitcher, so I figured I'd see fastballs. I was so excited that I swung at the first pitch and it was two feet off the plate. I had to gather myself. They had the infield in, and I was able to get enough wood on it to creep it through the infield."
Keisler, who was called up when closer Danny Graves was designated for assignment, was mobbed by teammates at first base.
"You always want to have something like that happen," said Keisler, who was 0-for-4 in limited appearances with the New York Yankees and San Diego Padres. "That was fun. It was good to get a little energy going."
Keisler (1-0) allowed one walk in two innings for the win. Ayala (2-3) allowed three hits in 2 1/3 innings and took the loss.
Austin Kearns led off the 14th with a drive to the warning track in center field that Brad Wilkerson ran down. Jason LaRue then singled softly to left-center. Luis Lopez followed with a double to right that Jose Guillen knocked down while trying to make a diving catch, setting up Keisler's at-bat.
The Nationals stranded a season-high 17 and went 3-for-17 with runners in scoring position.
"It's no more frustrating than the way it's been going lately," Washington manager Frank Robinson said. "We were winning these close games earlier. Now, we're not. We can't get the big hit. Until we get some hits with men on base, it's going to be frustrating."
The Reds won consecutive games for the first time since a three-game winning streak from April 16-18. They clinched their first series win since taking a three-game set against Houston from April 15-17. They then went 0-8-3 in 11 series.
Washington starter Livan Hernandez gave up six hits and three runs and struck out a season-high eight over seven innings while avoiding his first loss since April 19. He was trying to become the franchise's first pitcher to win at least seven consecutive starts since Pedro Martinez won eight in a row for Montreal in 1997.
Brandon Claussen of the Reds turned in his longest outing of the season and first start since spraining an ankle on May 10. He allowed seven hits and two runs with four walks and four strikeouts over six innings for his first win in four starts. His previous longest stint was 5 1/3 innings in his other win.
Hernandez threw 34 pitches in Cincinnati's big first inning. With one out on a caught stealing, he walked two batters and hit Adam Dunn with a pitch before Kearns lined a bases loaded double into the right field corner to make it 3-1.
That wiped out the 1-0 lead Washington took on Vinny Castilla's RBI-double to left-center with two outs. Ken Griffey Jr. kept the ball from going to the wall with a sliding stop, forcing Nick Johnson, who had been on first, to hold at third.
Pinch-hitter Marlon Byrd cut Cincinnati's lead to 3-2 with a bases loaded sacrifice fly in the fifth, and pinch-hitter Carlos Baerga singled to drive in Johnson from third with the game-tying run in the ninth. That cost David Weathers his second save in as many nights as the first Reds reliever to try closing since Graves' departure.
- The Nationals scored a run in the first inning for just the second time in 22 games this month.
- Lopez made his first career start for Cincinnati.
- Dunn struck out looking with the bases loaded and one out in third to extend to 57 his streak of consecutive failed chances to hit a sacrifice fly. Dunn hasn't hit a sacrifice fly since July 22, 2003.
- Carroll singled and doubled in his first two at-bats to snap a 3-for-20 slump.
- The Reds marked the 70th anniversary of the first night game in the majors, at Cincinnati's Crosley Field in 1935, by displaying one of the lights from that game on a pedestal in center field. The light still worked.
- Reds 1B Sean Casey left the game in the seventh after jamming his left shoulder trying to field Jose Guillen's grounder. He was to be re-evaluated Wednesday morning.