If all went right for the Washington Nationals, they could have celebrated an NL East title in Philadelphia last week.
Now, with their magic number still at one, the Nationals will get a chance to close out the East with the Phillies in town.
Washington goes for its first division title -- and the franchise's first in 31 years -- on Monday night in the opener of a season-ending three-game series.
With its magic number for clinching the East down to 5, Washington (96-63) could have won the division in Philadelphia, but it won two of three while second-place Atlanta swept Miami.
The surging Braves took two of three from the New York Mets over the weekend to again delay a Nationals celebration after Washington lost two of three in St. Louis. The Nationals, though, are still in good position to win the franchise's first division title since the Montreal Expos did in 1981.
"It's better to clinch it at home anyway," manager Davey Johnson said after Sunday's 10-4 loss.
While the Nationals would prefer to take care of business themselves -- Atlanta plays at Pittsburgh -- Johnson's club is also locked in a tie with Central champ Cincinnati for the best record in the NL and homefield advantage throughout the playoffs.
The Reds close out the regular season in St. Louis.
The Nationals, winners of two straight against Philadelphia after losing seven of eight, will give the ball to John Lannan (4-0, 4.23 ERA) on Monday.
The left-hander will make his sixth start this season, and his fourth since taking over Stephen Strasburg's spot in the rotation.
Lannan will go for a third consecutive win versus Philadelphia after going 1-12 with a 5.81 ERA in his first 16 starts in the series. He gave up two runs over 5 1-3 innings in Wednesday's 8-4 victory at Citizens Bank Park.
The Phillies (80-79) enter this series knowing it will be their last. It's been a difficult year for a club that was coming off a franchise-record 102 wins and a fifth straight East title.
All Philadelphia can do now is try to finish with its 10th consecutive winning record, and it'll turn to Kyle Kendrick (10-12, 4.08) to at least ensure a .500 finish.
The right-hander, though, is going up against a team that tagged him for a season-high three homers -- one apiece from Bryce Harper, Ian Desmond and Kurt Suzuki -- and five runs in two-plus innings on Wednesday.
"They put some good swings on some balls," Kendrick told the Phillies' official website.
Harper has been doing a lot of that lately, as he's batting .481 (13 for 27) with three homers and seven RBIs during a seven-game hitting streak. The 19-year-old hit his 22nd homer Sunday and is two shy of the major league record for teenagers set by Boston's Tony Conigliaro in 1964.
Shortstop Jimmy Rollins leads the Phillies with five homers and nine RBIs versus Washington this season. He's hitting .176 (6 for 34) against Lannan since 2009 after going hitless in three at-bats last week.
Washington needs to sweep to clinch the season series for a second consecutive year.
Copyright 2012 by The Associated Press
This story is from ESPN.com's automated news wire. Wire index
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