However, manager Matt Williams' club could have the pitching edge in Wednesday's series finale.
Los Angeles (78-61) fell 6-4 in Monday's opener before bouncing back with a 4-1 victory the following day. Clayton Kershaw threw eight strong innings to become baseball's first 17-game winner and Juan Uribe hit a two-run homer.
"We needed to get the W tonight," said Kershaw, whose team remained two games ahead of San Francisco for the NL West lead. "It was good to get it."
Los Angeles has taken 17 of 25 from Washington (78-59), which is seeking its first series win at Dodger Stadium since May 2005. The Nationals could be feeling good about their chances of accomplishing just that behind Jordan Zimmermann (10-5, 2.93 ERA).
The right-hander went 4-0 with a 2.21 ERA last month as Washington won each of his six starts. He allowed two runs and struck out eight over six innings to win 8-3 at Seattle on Friday.
"He kept pouring it in the strike zone, that's what he does," Mariners bench coach Trent Jewett told MLB's official website. "That's typically his outing. He's gonna keep coming after you, and he did it again tonight."
Zimmermann is 2-1 with a 5.61 ERA in five meetings against the Dodgers. He threw four strong innings but was removed following a three-hour rain delay in a 4-0 home win May 5.
Hanley Ramirez is 10 for 22 with three extra-base hits in their matchups and Matt Kemp is 6 for 14 with two homers.
The Dodgers counter with 24-year-old rookie Carlos Frias (0-0, 5.65), who's set to make his first big league start after getting called up Tuesday.
"We felt like he was a good guy for this 12 o'clock start," manager Don Mattingly said with first pitch scheduled for 12:10 p.m local time. "He's young. He doesn't need sleep."
Frias, who was sent to Albuquerque on Sunday before the rosters were expanded, allowed nine runs while posting a 1.05 WHIP over eight relief appearances spanning 14 1-3 innings with Los Angeles last month. The right-hander was 9-5 with a 4.63 ERA over 20 minor league starts this year.
Frias will need to be careful against Bryce Harper, who's starting to heat up. Harper provided Washington's offense Tuesday with his fourth homer in five games, a stretch over which he's gone 8 for 19.
"Bryce put a good swing on one," Williams said," but that was all (Kershaw) gave us. Anybody can beat anybody, but tonight he didn't give us any opportunities."
Denard Span could be back in the lineup after sitting out against Kershaw. Span, the team's leading hitter at .299, homered twice in Monday's victory and is 8 for 22 with four RBIs and seven runs scored in his last five games.
Adam LaRoche - mired in 1-for-23 slump - also missed Tuesday's defeat with lower back stiffness, leaving his status unclear.
The Dodgers, meanwhile, are hoping to see Ramirez get on track. The star shortstop is hitless in his last 16 at-bats and 4 for 32 in eight games since returning from the disabled list due to a strained right oblique.
Yasiel Puig has also struggled of late, going 2 for his last 30. He's been limited to one hit in 15 career at-bats against the Nationals.