David Ortiz scored on Jason Varitek's home run in the sixth inning of Wednesday's game.

AP photo / Manuel Balce Ceneta

WASHINGTON -- In the first game of this series against the Washington Nationals on Tuesday night, the Red Sox received a tremendous offensive performance from Jason Bay and Jacoby Ellsbury.

On Wednesday night, the Nationals pitching staff completely shut down the pair. But it really didn't matter that both Bay and Ellsbury went a combined 0-for-8, because on this night the multifaceted offense was picked up by two of its other members.

This time it was David Ortiz and Jason Varitek picking up the slack and helping Boston to a 6-4 victory at Nationals Park.

Ortiz provided a three-run homer and Varitek contributed a two-run blast in the winning effort. They came through in support of Red Sox starter Jon Lester, who went six innings and improved to 6-6 in his 15th start of the season.

"Good swing. Big swing," said manager Terry Francona of Ortiz's homer. "Same thing with Tek. That's about as far as you can hit a ball. David gave us our first three, Tek adds on with two and we pretty much made it hold up."

The road hasn't been a very good place for the Red Sox offense this season. The club entered Wednesday's game with a lowly .263 average away from Fenway Park for eighth in the league. In the first two games of this series, the offense has come alive.

"It's a nice feeling to find ways to win on the road because it has been tough for us," said Francona. "When you win a couple, even with a veteran team, you see more confidence."

Following Boston's 11-3 victory on Tuesday, it was Washington that pushed across a run in the bottom of the second inning to take an early lead. Nationals starter Craig Stammen kept the Sox stymied through the first three innings of perfect baseball.

 In the fourth, however, the Sox figured out Stammen.

Dustin Pedroia lead off with a double and with one out Kevin Youkilis drew a walk. Jason Bay struck out swinging before Ortiz crushed a three-run homer to deep center field to give Boston a 3-1 lead.

It was Ortiz' first three-run homer since last September, and his first road homer of the season. He now has 1,002 career RBI, and is four home runs shy of 300 career homers.

Due to interleague play and the loss of the DH at the National League park, Ortiz played first base Wednesday night. He was removed from the game in the sixth inning and replaced by Mark Kotsay. Less than 10 minutes after the game, Ortiz left the clubhouse already showered and in street clothes and would not talk with reporters.

Either way, his offensive performance Wednesday night, and of late, has been crucial for the Sox.

"He's had a good three weeks," said Francona. "He's controlling the bat very well. What's been a little hard is getting to interleague with a day off and we're trying to keep everyone healthy. The last thing I want to do is get in David's way of getting hot. He's to a point where he understands what happened the first two months was very difficult, and he doesn't feel like that hitter anymore."

Francona understands that when Ortiz looks at his stats he still sees a .219 average. But if he continues to hit the way he has of late, Ortiz will be just fine.

"His spirits seem good and he's swinging the bat very well, and if we get David Ortiz the last couple of months, what happened the first couple won't matter," Francona said.

The Red Sox added to their lead in the top of the fifth on Pedroia's two-out RBI single for a 4-1 advantage. Boston kept the offense going when Varitek crushed a two-run homer into the upper deck of the bleacher seats in right-center field as the Sox increased their lead, 6-1.

"I hit it pretty good," said Varitek. "And at a good time, so it was good."

Lester began to tire and allowed two more runs in the bottom of the sixth inning as the Nationals cut their deficit, 6-3.

The Sox' southpaw was finished after six innings and allowed three runs on six hits with two walks and six strikeouts. He threw 103 pitches, 67 strikes.

Reliever Justin Masterson entered in the bottom of the seventh and surrendered one run on two hits, including a RBI triple by the Nationals' Cristian Guzman.

Washington had an opportunity to cut its deficit to one when Ryan Zimmerman launched a ball to deep left-center field. Fortunately for Boston, Ellsbury, in an all-out sprint, caught up to the ball and made the catch before crashing into the wall at the 377-foot mark in left-center field to end the inning.

The Nationals threatened again the bottom of the eighth inning with two on and two outs before reliever Hideki Okajima struck out pinch-hitter Ronnie Belliard to end the threat.

With the Red Sox holding a two-run lead, closer Jonathan Papelbon emerged from the bullpen in the bottom of the ninth to register his 17th save of the season.

jmcdonal@projo.com