Opposite dugout: First-place Diamondbacks have yet to lose a series

Manager: Torey Lovullo (2nd season)

Record: 24-12

Last 10 games: 5-5

Who to watch: CF A.J. Pollock (.308 with 11 HR, 32 RBIs), RF David Peralta (6 HR, 19 RBIs), SS Nick Ahmed (6 HR, 18 RBIs), RHP Matt Koch (2-0, 2.13 ERA), RHP Zack Greinke (3-2, 4.10 ERA), RHP Brad Boxberger (2.25 ERA, 11 saves)

Season series vs. Nationals: 2-1

Pitching probables:

May 10: RHP Tanner Roark (2-2) vs. RHP Zack Greinke (3-2), 9:40 p.m., MASN2
May 11: RHP Max Scherzer (6-1) vs. Matt Koch (2-0), 9:40 p.m., MASN2
May 12: RHP Stephen Strasburg (4-3) vs. TBA, 4:05 p.m., MASN
May 13: RHP Jeremy Hellickson (1-0) vs. RHP Zack Godley (4-2), 8:08 p.m., ESPN

Inside the Diamondbacks:

The Diamondbacks just keep chugging along. They possess the National League's best record at 24-12 and their 3 1/2 game lead over the Rockies in the NL West is the largest cushion in the majors. The Snakes' strength is their pitching - they rank second in the majors with a 3.17 ERA, a .220 batting average against and 123 runs allowed. Further proof that the bats haven't yet caught up with the arms: Arizona is prospering despite only an average of 4.29 runs per game in offensive support, which ranks 17th in the bigs. Arizona is 18-1 when scoring four or more runs. The D-backs have yet to lose a series this season, winning 10 of 12 and splitting the other two, both against the division rival Dodgers.

The Diamondbacks hope the return of ex-National Steven Souza Jr. to the outfield rotation after missing six weeks with a right pectoral muscle injury will add some thump to the lineup. He hit 30 homers last year for the Rays before an offseason trade. So far, Arizona has been thankful for the power bat of center fielder A.J. Pollock while it waits for slugging first baseman Paul Goldschmidt to round into form. Pollack leads the team with 11 homers and 32 RBIs, while Goldschmidt has been slow out of the gate with a .227 average, four homers and 12 RBIs. Right fielder David Peralta has been dangerous, putting together a .288/.380/.500 slash line with six homers and 19 RBIs. Third baseman Daniel Descalso and shortstop Nick Ahmed have each driven in 18 runs.

Veteran right-hander Zack Greinke, who starts tonight's series opener, has worked at least six innings in four of his seven starts. But he's also given up seven homers in 41 2/3 innings, which is a red flag. Greinke missed the Nationals when the teams met late last month, but he's 5-1 with a 1.49 in seven career starts against Washington. Righty Matt Koch, Friday's starter, has worked at least six innings in three of his four starts, adding some stability to the injury riddled D-backs rotation. He's coming off 6 1/3 innings of six-hit one-run ball against the World Series champion Astros on May 6. At home, he yields only a .194/.275/.403 slash line. Saturday's Diamondbacks starter is still listed as TBA, but righty Zack Godley gets the nod in Sunday night's finale, which will be nationally broadcast on ESPN. Working as a fifth starter, Godley won four of his first five decisions in 2018; but the Diamondbacks are asking more of him following injuries to Taijuan Walker and Robbie Ray.

Brad Boxberger has locked down the ninth inning with 11 saves in 12 tries and a 2.25 ERA.