Ian Kennedy looks to guide Arizona to a fourth straight victory while Chicago rookie phenom Anthony Rizzo tries to stay hot in the opener of a three-game series Friday at Wrigley Field.
The defending NL West champion Diamondbacks (42-43) blame inconsistency for their four-game division deficit. After sweeping the Cubs in a three-game set June 22-24, Arizona lost eight of its next 10 to drop four games below .500.
It recovered to take three of four from the division-leading Los Angeles Dodgers before the All-Star break to close the gap.
"We've had good stretches this year; we played good in June," manager Kirk Gibson told the team's official website. "We've had tough stretches. You just have to continue to power on. What choice do we have? It's been a struggle.
"We've endured a lot and we're in good shape going into the second half."
Gibson said it's disappointing Arizona has gotten off to a rough start coming off a division title, but his team's confidence still is high.
"We know we can go on a run, we have in the past," Gibson said. "We've made it harder on ourselves, let's be realistic, but we still believe."
Rizzo has given the Cubs plenty of reason to believe the future is bright. Since being called up from Triple-A Iowa on June 26, Rizzo is hitting .354 with four homers and four doubles with Chicago going 8-4 in those 12 contests.
The Cubs (33-52) possess one of the worst records in baseball in their first season rebuilding under Theo Epstein's regime, but Rizzo has provided a pick-me-up.
Chicago ended the first half with a 7-0 win over the New York Mets on Sunday.
"(Rizzo) has changed everything," Alfonso Soriano told the team's official website. "Batting third, hitting homers, defense - I hope the way he plays and the way we play, I hope we continue that way in the second half."
The Cubs have won five of the last six meetings with the Diamondbacks at Wrigley Field, a pattern Kennedy will be out to change.
Kennedy (6-7, 4.26 ERA) is 1-2 with a 5.06 ERA over his last five starts after giving up four runs in seven innings of Arizona's 8-6 loss to San Diego on July 4, though he's gone at least seven innings in three of his last four starts.
The only outing he failed to do so was against the Cubs on June 23, when he allowed five runs and 10 hits in 4 1-3 innings of the Diamondbacks' 10-5 victory.
The right-hander is 1-1 with a 6.66 ERA in four career starts versus Chicago, and he'll face Paul Maholm, who's looking for a third straight strong outing.
Maholm (6-6, 4.57) capped a rough seven-start stretch in which he went 0-4 with a 6.50 ERA by giving up seven runs in 3 1-3 innings while opposing Kennedy, but he's been much better since.
The left-hander allowed four hits in 8 1-3 innings to beat Houston 4-0 on June 29, then gave up one run in six innings of a 5-1 win over Atlanta on July 4. He also pitched an inning of relief Sunday.
The Cubs, though, have lost four straight and six of the last eight overall meetings with the Diamondbacks.