Arizona right-hander Merrill Kelly will look for his fifth win in as many starts as the Diamondbacks attempt to complete a three-game sweep of the host Washington Nationals on Thursday.

Kelly (7-3, 2.80 ERA) hasn't lost since April 22 and is 6-0 in his past seven starts. During that run, he has posted a 2.44 ERA with 52 strikeouts and 11 walks in 44 1/3 innings. He has given up two earned runs or fewer in nine of his 12 starts overall.

Last time out, Kelly gave up two runs and five hits over seven innings of a 3-2 win against the Atlanta Braves on Friday. He struck out eight and walked three. Over his past two starts, he has allowed just three runs while fanning 18 in 13 1/3 innings.

"Having Merrill on the mound with his stuff, his mindset, his mentality -- that dog mentality -- it's easy to feed off," teammate Christian Walker said. "When your guy is out there, putting himself on the line and coming through in big moments, you have to get him runs."

Kelly, 34, is 3-0 with a 3.79 ERA in three career starts against Washington. He beat the Nationals on May 5, throwing seven innings of one-run ball and striking out 10 during Arizona's 3-1 victory.

The Nationals will counter with their top pitcher to date, right-hander Josiah Gray (4-5, 3.09 ERA). Gray, 25, is 2-0 with a 3.18 ERA in his past five starts. Control problems have limited his length in recent games as he has walked 11 batters in 14 1/3 innings in his past three outings.

Gray struggled against Philadelphia on Friday, giving up four runs over 5 1/3 innings during a no-decision. He struck out four, walked two and served up two home runs. The Phillies got to Gray for three runs in the sixth, but he left with a 7-3 lead.

"Looking at the outing as a whole, I was able to limit loud contact until the last four batters," Gray said. "I just wanted to keep the team in the game. They gave me a really big lead. And thankfully they did, cause this could've gotten ugly quick."

Gray is 1-1 with a 3.48 ERA in two career starts vs. Arizona. He allowed three runs in five innings during a loss Kelly and against the Diamondbacks in Phoenix on May 5.

Corbin Carroll had four hits, including a two-run homer, Zach Davies pitched into the seventh inning and the Diamondbacks took the middle game of the series 6-2 on Wednesday night.

Emmanuel Rivera had three hits and two RBIs for the Diamondbacks, who have won eight of their past 10 games. Leadoff batter Ketel Marte had three hits and a walk and scored twice, including in the first inning, when he opened the game with a double.

"He's such an impact player," manager Torey Lovullo said. "When he's drawing walks -- which he's been doing for the past month -- and slugging the baseball, he can just redirect the game with one swing."

Joey Meneses and Dominic Smith had two hits each for Washington, which has lost four in a row and will now try to avoid the sweep.

"These guys are good," Nationals manager Dave Martinez said of the Diamondbacks. "They play the game the right way. They run, steal bases, they put the ball in play, they play good defense. We've just got to focus on what we do good, and that's basically the same."

--Field Level Media