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The Washington Nationals boast the National League's three top hitters in terms of batting average in Daniel Murphy, Ryan Zimmerman and Bryce Harper.

The trio helped the Nationals produce the National League's most productive offense in the first half, and the NL East leaders look to continue producing consistently Friday night when they visit the Cincinnati Reds for the opener of a three-game series.

Coverage begins with Reds Live at 6:30 p.m. on FOX Sports Ohio

Murphy is hitting .342 in his second season with the Nationals and is leading the league after being edged by one point in the batting race by Colorado's DJ LeMahieu last season.

Zimmerman is hitting .330 and is on track to finish above .300 for the first time since hitting .307 in 2010. He also is producing after missing a combined 215 games in the previous three seasons.

Harper is third at .325 after batting a career-worst .243 last season. Harper also is among 14 players with at least 20 homers in the NL and his 65 RBIs are five shy of NL co-leaders Nolan Arenado and Marcell Ozuna.

The trio is part of an offense that leads the National League with a .277 average, 486 runs, 472 RBIs, and a .345 on-base percentage.

Zimmerman and Murphy have not spent a day under .300 this season while Harper's average has been over .300 every day except for April 9.

Because of their potent hitting trio, the Nationals have held sole possession of first place every day since April 18 when they improved to 8-5. Washington entered the break with five wins in its last seven games after Murphy, Zimmerman and Harper were a combined 4-for-12 with four RBIs in a 10-5 win over the Atlanta Braves on Sunday.

"They're not called the 'heart of the order' for nothing, cause that's the life source for you, is your heart," manager Dusty Baker said after Murphy's 10th-inning single gave the Nationals a 5-4 victory last Friday over Atlanta.

Zimmerman, Murphy and Harper hit a combined 53 homers for the Nationals, who are tied with the Reds with 125 homers. Zimmerman has 19 of those homers and his next one will be his 235th career homer, which breaks a tie with Vladimir Guerrero for first place on the franchise's all-time list.

The Reds were outscored 26-14 and lost two of three in Washington June 23-25. While Joey Votto was 2-for-11 in that series, Zack Cozart did not play due to a strained right thigh.

Cozart is hitting 8-for-28 since being activated June 30 and .309 overall. The Reds are 6-4 in their last 10 games since their All-Star shortstop returned from his second DL stint and entered the break at 39-49 following a 2-1 win at Arizona on Sunday.

Votto is third in the NL RBI race, and in his last nine games, he is batting .355.

Cincinnati also is 9-6 in its last 15 games since an 18-3 loss at Washington on June 24. The blowout loss to the Nationals was part of a stretch of 13 losses in 14 games, but the Reds bounced back decently and posted seven more wins in the first half this year after entering the break at 32-57 last season.

"The quality of our at-bats, not giving in, finding ways to scrap and get ourselves back into games we're behind has really been the calling card of the club, I think, in these close to 90 games of the season," Reds manager Bryan Price said. "That's what I expect. That's the only expectation I have, that guys show up prepared to play and they do that every day."

The Reds own the National League's worst ERA at 5.05 but also slightly improved their pitching in the final weeks of the first half. After Homer Bailey gave up a run in 6 2/3 innings Sunday, Cincinnati has posted a 3.99 ERA in its last 15 games.

Besides their potent lineup, the Nationals' rotation was 38-23 with a 3.71 ERA in the first half. The only reason Washington's team ERA of 4.16 is sixth in the NL is because of a bullpen that has posted a 5.16 ERA.

Gio Gonzalez (7-4, 2.86 ERA) takes the mound to start the second half for Washington and looks to get better run support and a win. He lost his last three starts despite posting a 2.37 ERA because the offense scored eight times, with four of those runs occurring in the bottom of the ninth June 26 against the Chicago Cubs.

Gonzalez last pitched July 6 in a 5-2 loss to the Atlanta Braves and allowed three runs and seven hits in six innings. It marked the 16th time in 18 starts this season the left-hander allowed three runs or less.

Gonzalez did not face the Reds in the last series between the teams and is 3-2 with a 2.98 ERA in eight career starts against them. Half of those starts occurred in Cincinnati where Gonzalez is 1-2 with a 4.63 ERA.

Tim Adleman (5-6, 4.71 ERA) starts for the Reds. He lost his final two starts before the break and is 1-4 with a 5.23 ERA in his last six starts.

Adleman finished the first half by allowing four runs (three earned) and six hits in five innings of a 6-3 loss at Arizona. He allowed a solo homer to Paul Goldschmidt and 10 of the 19 homers hit against him are in his last six outings.

Adleman has never faced the Nationals.