Cincinnati looks to stay hot Tuesday night with help from starter Tony Cingrani as he opposes Patrick Corbin, who has struggled on the road lately.
The Reds (71-54) have won 10 of 13 to move a season best-tying 17 games over .500 in their quest to overtake St. Louis and Pittsburgh in the Central. Brandon Phillips had three hits and Ryan Ludwick drove in his first run of the season in Monday's 5-3 win over Arizona.
"We've been playing pretty well since I came back,'' said Ludwick, who returned from shoulder surgery Aug. 12. "We beat the team that's behind us in the wild-card standings, so that's a good start to the series.''
Manager Dusty Baker believes the defending division champs are more than capable of repeating.
"Like I've said, our best days are ahead of us,'' Baker said. "We've just got to keep winning in the meantime.''
The Diamondbacks (64-59) had won five of six prior to Monday, but they fell six games behind the Reds for the league's second wild-card spot. They remained 7 1/2 games back of the Los Angeles Dodgers in the West.
"We're hoping to win the next three (of this series). That's our goal,'' catcher Wil Nieves said.
Arizona, which got two hits from Paul Goldschmidt and a pair of RBIs from Martin Prado on Monday, will look to get back on track as Corbin (12-3, 2.48 ERA) takes the mound.
Corbin allowed more than three earned runs for only the fourth time in 24 starts Wednesday, giving up four and a season worst-tying nine hits through seven innings before Arizona beat Baltimore 5-4 in 14.
"I just wanted to go out there and throw up some zeros and see how many innings I could go and try to stay in the ballgame as long as I could," Corbin told the team's official website.
The left-hander has pitched at least six innings in all but one of his outings, including when he gave up one run - a solo homer to Jay Bruce - and three hits in eight frames of the Diamondbacks' 4-3 win over the Reds on June 22.
Corbin, though, is just 1-2 with a 5.40 ERA in his last five road starts, but the Reds rank in the bottom third of the majors hitting .244 against left-handers.
The Diamondbacks, meanwhile, rank among baseball's leaders with a .266 average versus lefties, and they'll face another in Cingrani (6-2, 2.78).
Cingrani has been excellent since rejoining the rotation July 3 after five relief appearances, going 3-2 with a 2.12 ERA in eight starts. The 24-year-old gave up one run and struck out nine over 6 1-3 innings of Thursday's 2-1 win at Milwaukee, giving him 100 strikeouts in 86 2-3 innings over 15 starts on the season.
"He's confident. He's not intimidated by anybody,'' Baker said. "This is how you want your players to be, especially rookies. He wanted to make this team out of spring training. He's full of determination and desire, and a lot of confidence.''
Cingrani has yet to face the Diamondbacks, who have dropped seven of the last nine meetings with the Reds.