Nats Game Night – at Phillies, 7:05 p.m.

Starters » Ross Detwiler (10-6, 3.10 ERA) vs. Cole Hamels (15-6, 3.05 ERA)

When » Tuesday, 7:05 p.m.

Where » Citizens Bank Park, Philadelphia

TV » MASN HD

Radio » 106.7 The Fan FM, WFED 1500, WHFS 1580

Nationals manager Davey Johnson will still start three left-handed pitchers against the Philadelphia Phillies this week during a three-game series. But he decided to flip the order, making the announcement on Tuesday morning. Ross Detwiler will make the opening start in Game 1 before giving way to John Lannan for Game 2 on Wednesday. Gio Gonzalez goes for Washington in the series finale on Thursday.

The Phillies have a .692 OPS against left-handed pitchers in 2012, which ranks 22nd overall. But the Nats have a tough task tonight against lefty Cole Hamels, who is 12-5 with a 2.48 ERA in 23 career starts against Washington.

Detwiler’s had a good run against Philadelphia himself with 14 1/3 scoreless innings, including a Sept. 20, 2011 start where he took a shutout into the eighth inning. Detwiler hasn’t struck out more than five batters in a game since April 20 when he fanned seven Miami Marlins so the key for him, as always, is to avoid walks. He’s issued just one free pass in six of his last eight starts. No surprise his ERA is even better than Stephen Strasburg’s (3.16).

The Nats have nine games left in the regular season and their magic number to clinch the National League East title is down to five. The schedule is against them, however, with this road series against the rival Phillies followed by three more in St. Louis over the weekend. And the Cardinals (83-71), while a comfortable 3 ½ games ahead of Milwaukee and the Los Angeles Dodgers for the final N.L. wild card spot, can’t exactly afford to coast.

Meanwhile, the second-place Atlanta Braves (88-65) have home games against the woeful Marlins and Mets and it’s the final regular season homestand for future Hall-of-Fame third baseman Chipper Jones. Safe to say the good folks at Turner Field will be excited. The Braves clinch a playoff spot with one more win and new ace Kris Medlen on the mound tonight. Their magic number to host the N.L. wild card game is four over the Cardinals.

The division is still a long shot for them. Even if Washington finished a disastrous 0-9 then Atlanta would still have to go 6-3 to steal the title outright. Even a 3-6 finish by the Nats means the Braves must go 8-1 just to force a playoff.

Here are today’s lineups:

Nats

RF – Jayson Werth

CF – Bryce Harper

3B – Ryan Zimmerman

1B – Adam LaRoche

LF – Michael Morse

SS – Ian Desmond

2B – Danny Espinosa

C – Kurt Suzuki

RHP – Ross Detwiler

Phillies

SS – Jimmy Rollins (S)

CF – John Mayberry

2B – Chase Utley (L)

1B – Ryan Howard (L)

C – Carlos Ruiz

RF – Domonic Brown (L)

LF – Darin Ruf

3B – Kevin Frandsen

LHP – Cole Hamels

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