Miami Marlins (49-58) at Washington Nationals (63-43), 7:05 p.m.

Probable Starting Pitchers: Miami - Mark Buehrle (9-10, 3.60) Washington - Jordan Zimmermann (8-6, 2.28)

(Sports Network) - The first-place Washington Nationals turn to streaking righty Jordan Zimmerman to maintain their lead tonight when they host the visiting Miami Marlins in the third game of a four-game weekend series.

The Nationals saw their margin in the National League East Division trimmed to two games on Friday after they split a doubleheader with the Marlins and the second-place Atlanta Braves defeated Houston, 4-1.

Zimmerman, a 26-year-old Wisconsin native, has won five straight decisions across seven starts since last losing at Baltimore on June 22.

He allowed a run on five hits in six innings of his last start - on July 28 at Milwaukee - and saw his earned run average plunge to a season-low 2.28.

In the seven starts since the loss, he's allowed just six runs on 35 hits in 44 innings.

The third win in the 5-0 stretch came against the Marlins at Miami, where he tossed six scoreless innings of four-hit ball in a 5-1 Washington win.

Zimmerman hasn't allowed more than three runs in a game since dropping a 5-3 verdict at Miami on May 28.

The Marlins counter with veteran lefty Mark Buehrle, who can stay unbeaten against the Nationals in his fourth career start.

He was a 2-1 winner against Washington on July 14 in Miami after allowing a run on six hits in seven innings with seven strikeouts.

He's 0-2 with a no-decision in three starts since while working 14 1/3 innings and giving up 19 hits and 12 runs against the Chicago Cubs and Atlanta twice.

Buehrle, who turned 33 in March, is in the first year of a four-year free agent deal that could pay him as much as $54 million.

He won 161 of 280 decisions for the Chicago White Sox over 12 seasons in the American League, including a fifth-place finish in Cy Young Award voting in 2005 after he went 16-8 with a 3.12 ERA in 33 starts.

On Friday, Josh Johnson tossed 8 2/3 outstanding innings, outdueling Gio Gonzalez in the process, as the Marlins took down the Nationals, 5-2, to earn a split of a doubleheader at Nationals Park.

Johnson (7-7) threw 76 of his 115 pitches for strikes, allowed two runs and scattered five hits to go with nine strikeouts and no walks. He also had two hits at the plate in the victory. Steve Cishek got the last out to record his sixth save of the season.

Carlos Lee knocked in three runs and Jose Reyes went 3-for-5 with a pair of runs scored to extend his career-best hitting streak to 22 games. Greg Dobbs added an RBI base hit for the Marlins, who snapped a two-game skid.

Ryan Zimmerman drove in a run for the division-leading Nationals, who took the opener, 7-4, on the strength of a three-hit game from Adam LaRoche and a strong performance on the mound from John Lannan.

Gonzalez (13-6) took the loss after allowing four runs on nine hits over eight innings. He fanned 10 and did not issue a walk.

"Gio threw great," Zimmerman said. "Just one of those games where he ran into a pitcher that threw a little bit better. Unfortunately we just couldn't get to their guy."

The Marlins posted a three-game sweep of Washington in Miami from May 28-30.

The Nationals have not won the season series since 2007.