With not much of a chance at reaching the postseason, the game set whey that makes them a dangerous club.

The Nats look to get a jump on their eventual role of spoiler this evening when they try to win four straight games over the Phils for the first time since relocating to Washington DC.

After taking the final two games of a series in Washington that bridged the months of May and June, the Nationals took care of business again last night at Citizens Bank Park in this opener. They got to 13-game winner Cole Hamels early and rode the arm and bat of Livan Hernandez to a 4-2 win.

Hernandez gave up just one unearned run on four hits over 6 2/3 innings and added a pair of RBI singles to help Washington avoid an eighth straight loss in Philadelphia while moving to 4-4 on a 10-game road trip.

"We were patient. We made (Hamels) get the ball up," said Washington manager Davey Johnson.

The Nationals, who are 13-36 against the Phillies in the past 49 meetings, won for only the fourth time in their last 25 trips to Philadelphia, but a victory tonight would give the franchise a four-game winning streak in this series for the first time since the Montreal Expos swept a four-game set from Aug. 25-28, 2003.

Philadelphia will try to prevent that from happening after getting runs batted in from Hunter Pence and Wilson Valdez on Friday night. Hamels, meanwhile, was charged with three runs on six hits and four walks, striking out five over five innings.

"When you're not able to loosen up and get things going, it makes it a little bit tougher," Hamels said. "They found some holes, and that's just kind of the breaks."

Philadelphia returned home following a franchise-best 10-game road trip in which it went 9-1, but last night's loss shrunk its lead over Atlanta for first place in the National League East to 7 1/2 games.

Nats pitcher John Lannan will also be trying to build a winning streak versus the Phils after beating them for the first time in his career back on June 1.

The left-hander had dropped his first 10 decisions to the division leaders before holding them to one unearned run over 5 1/3 innings of a 2-1 triumph. Lannan still owns a career 5.96 earned run average against Philadelphia in 14 starts.

Lannan has won three of his past four decisions overall, but did not factor into a 3-1 victory at Colorado on Sunday. He pitched six innings of one-run ball, working around six hits and four walks with three strikeouts. The 26- year-old is 8-7 with a 3.56 ERA in 24 starts this season.

Roy Oswalt will make his second start since a six-week stint on the disabled list because of a back injury. The Phillies right-hander returned to action on Sunday in San Francisco, but took a loss after giving up three runs on 12 hits over six innings. It was Oswalt's third straight loss and he has dropped seven of eight decisions since a 3-0 start.

The 33-year-old is 4-7 with a 3.84 ERA in 14 starts and was beaten by the Nationals when he last faced them on June 1. He gave up two runs over five innings.

In 18 career meetings with the Washington franchise, including 16 starts, Oswalt is 5-4 with a 3.12 ERA.