Arizona's surge has put it in contention in the tight NL West race.
The Philadelphia Phillies haven't done the Diamondbacks any favors by seemingly strengthening their rivals.
The Diamondbacks look to match their longest winning streak of the season for the second time in two weeks by becoming the latest team to beat Phillies ace Roy Halladay on Saturday night.
Arizona (55-51) has won four in a row and 11 of 14 after opening this three-game set with Friday's 4-2 victory at Philadelphia (47-59).
The Diamondbacks were seven games out of first place in the West before that run, and have since closed within two of division-leading San Francisco, which is in front of second-place Los Angeles by one-half game.
The Phillies continue to complicate matters in the West, especially for Arizona. They sent right-hander Joe Blanton to the Dodgers for future considerations after he was claimed off waivers Friday.
They already dealt outfielders Shane Victorino and Hunter Pence to the Dodgers and Giants, respectively, prior to Tuesday's non-waiver trade deadline.
The Diamondbacks took advantage of Blanton's departure as Kyle Kendrick gave up three runs in four innings. Philadelphia has lost five of seven and is mired at the bottom of the NL East after winning it five years in a row.
"Obviously, it's difficult," Kendrick said. "But we have two months left. We want to try to win some games."
Halladay (4-6, 4.33) probably shares that sentiment. The two-time Cy Young Award winner is 1-6 with a 5.43 ERA in 11 starts, including an 0-3 record and 4.91 ERA in five home outings.
The right-hander was charged with a 6-2 loss at Atlanta on Sunday, surrendering three runs and six hits - two homers - with seven strikeouts in six innings. He's lost three decisions in a row over five starts thanks to a 7.20 ERA.
Halladay is facing the Diamondbacks for the first time this year after he was the hard-luck loser in a 3-2 home defeat Aug. 16. He tossed an eight-hitter while tying a career high with 14 strikeouts after winning each of the previous three meetings.
Justin Upton is 6 for 15 with two homers and four RBIs in four meetings with the Phillies this year after collecting two hits Friday, including his 100th career homer.
Jason Kubel also had a solo shot after enduring a 2-for-19 slump over the previous five games. The outfielder is 10 for 26 with three homers and six RBIs in seven career meetings with the Phillies.
The Diamondbacks are scheduled to turn to Joe Saunders (5-7, 3.62), who has a 2.44 ERA in eight road starts, but just a 1-2 record to show for it. He hasn't won as the visitor since beating Miami on April 27, going 0-2 with a 3.53 ERA over the six following games.
The left-hander's last two outings came at home, which he split. He was charged with a 5-1 loss to New York on Sunday, surrendering four runs and eight hits in seven innings while issuing three walks, matching his season high set two weeks ago.
"The walks hurt, that hurt me," Saunders told the team's official website.
Saunders is 1-2 with a 5.26 ERA in four stats against the Phillies, losing both last year while being tagged for 11 runs with 11 strikeouts in 11 2-3 innings.