Nationals left fielder Brian Bixler makes a circus catch after taking a circuitous route to this fly ball off the bat of Ross Gload in the ninth inning. (Matt Slocum/AP)

A few players in the Washington Nationals clubhouse have discussed among themselves the possibility, more vividly alive each day, that they can finish with a record better than .500, the best since baseball returned to Washington. “It’s very reachable,” second baseman Danny Espinosa said.

The Nationals can afford to lose only once in their final seven games, but their recent surge and stunning takedown of the Philadelphia Phillies provides reason to ask: Why not? Wednesday, Espinosa and Wilson Ramos delivered the Nationals’ latest salvo at the Phillies, combining for two homers and five RBI in a 7-5 victory at Citizens Bank Park.

The Phillies planned on resting for the playoffs. The Nationals have them reeling. Washington has won eight of 10 against its divisional bully, including three games in the past two days, and leads the season series, 9-8. At worst, the Nationals will have played the Phillies to a draw this season.

“Tomorrow’s the big one,” Manager Davey Johnson said. “I don’t want them to even the [season] series.”

Before he said that, Johnson had just stopped talking about how he’s liking the visiting manager’s office here “more and more.” The Phillies built their reign over the National League East on the Nationals’ backs, going 51-21 against them from 2007 to 2010. Has the Nationals’ recent success against Philadelphia erased the effects of that supremacy? Well, even John Lannan is beating the Phillies.

Lannan earned his second career win against the Phillies in his 17th try, allowing three runs in five innings. He also earned the 10th win of his season, a new career best. He teetered in the second, allowing five consecutive singles that gave the Phillies two runs and gave him a bases-loaded, one-out jam. It was the kind of situation that had ruined him in the past at Citizens Bank, where he had never won.

“I just had to keep executing pitches,” Lannan said. “One pitch at a time.”

Lannan escaped that mess with two popups and then allowed just one run the rest of the way. Craig Stammen added two scoreless relief innings, and Henry Rodriguez, with Drew Storen resting after closing two games Tuesday, earned the first save of his career.

The towering flyball Espinosa hit into the right field seats off Vance Worley, his college teammate at Long Beach State, provided the tying and go-ahead runs in the sixth inning. The two-run homer gave Espinosa 21 for the season, a new franchise record for a rookie. Among rookie second basemen, only Dan Uggla, with Florida in 2006, has ever hit more.

The homer also added another layer to the Nationals’ surge against the Phillies. Against the Phillies this year, Espinosa is 20 for 59 with seven homers, three doubles, six walks and 15 RBI in 17 games.

“I enjoy playing them,” Espinosa said. “They’re a good team. I think everybody enjoys playing a team like that. There’s a lot of people in the stands. It’s just a fun team to play.”

In the second inning, Ramos crunched his 14th home run, a two-run line drive that screamed into the first row above the scoreboard in right field. In a three-run eighth, he added an RBI single. Atlanta Braves first baseman Freddie Freeman is the only NL rookie besides Espinosa with more homers than Ramos.

On Wednesday, the 24-year-old rookies teamed up to topple the Phillies, who played without Ryan Howard and Hunter Pence as both nursed injuries. The Nationals played without Jayson Werth.

The Nationals won on consecutive days at Citizens Bank Park for the first time since April 7, 2005. They also clinched the series, something they had not done here since April 2008. The Nationals have played the Phillies tougher than any team in the majors, with the intent of reversing their miserable history against them.

“I don’t want a team coming in and just steamrolling us,” Espinosa said. “I want to play them hard. I want to beat them. I know we can beat them. We’re showing that. . . . It just shows what we can do, what this team is capable of doing. I’m pretty sure the Phillies are the best team in baseball, and we’ve played them really well.”

Said Lannan: “They’re the NL East champions. You’ve got to take them down. It’s definitely a step in the right direction. Looking forward to next year, it’s definitely huge.”

The Nationals, after they sputtered to begin September, have spent the previous week distancing themselves from much of their losing past. The won their 75th game Wednesday night, already two more than any Nationals team since 2005. They still have a chance for the best record since baseball returned to Washington — they can finish 81-80 if they go 6-1 over the next week. (A rain cancellation has forced the Nationals to play 161 games this year.)

“We want to get to .500,” Lannan said.

Wednesday, the last out dribbled, fittingly, to Espinosa. He made an easy, charging play and lined up to shake hands. Ramos chatted with Rodriguez, who struck out Jimmy Rollins on a 100-mph fastball to highlight a 1-2-3 inning. “I told him he only has 602 left to catch Mariano Rivera,” Ramos said.

The Phillies retreated to their clubhouse having lost five straight but with bigger aspirations in mind. The playoffs await for them. Next year when they play the Nationals, who knows if these games will stay with them, or if it will matter. The Nationals can at least hope.

“I think they know the way we’ve played this year,” Johnson said. “I think we’ve played them as tough as anybody they’ve played. I’m sure they’re fully aware of that. The last few games, Charlie [Manuel]’s thrown everything at us. They’re not important games to them, but they also want to end on a good note. So in a way, they are important games.”