Acquired on July 24 in a four-player deal with Houston, Rodriguez has gone 0-1 in two starts for Pittsburgh on the road. After a shaky Pirates debut against his former team on July 28, he settled down in his most recent start, limiting the Reds to three runs in seven innings.
"I've had my eyes on him for awhile," Pirates manager Clint Hurdle said. "He competes. He's been tough to hit, on any team that I've had. He's been tough to beat. I really feel that him getting an opportunity now to make a change, get to a [new] club, maybe a fresh start, I think it's going to help."
Saunders, meanwhile, is seeking just his second road win of the season, as the D-backs dropped his last five outings away from Chase Field. In those starts he is 0-3 with a 3.34 ERA. The lack of road wins, though, hasn't been all entirely on Saunders, as he has notched eight quality starts in nine road appearances and a 2.48 ERA.
In his most recent start, Saunders was the recipient of some bad luck and a heavy dosage of Roy Halladay. Saunders held the Phillies to two runs in 6 1/3 innings, but the D-backs still ended up losing, 3-0, after Halladay turned in seven scoreless innings.
"My career numbers against Roy are probably not that good," Saunders said after that game. "I think I'm 0-4 with, like, a 2.00 ERA against that guy. It seems like he brings his 'A' game against me for some reason. ... I just tried to keep us in the game as best I could."
The Pirates will go for the series win on Thursday after taking two of three, including Wednesday's 7-6 win.
The D-backs have dropped four of their last five, a stretch that comes shortly after a three-game sweep of the Dodgers that had them just 2 1/2 games out of first place in the National League West. Arizona now enters Thursday's game five behind division-leading San Francisco.
D-backs: Ziegler leads in double plays
Right-hander Brad Ziegler leads all relievers when it comes to getting batters to ground into double plays, inducing 13 this season, ahead of the Rockies' Josh Roenicke (11) and the Rangers' Robbie Ross (10).
Ziegler also leads the Majors with a 9.89 ground ball-to-fly ball ratio, and his 13 double plays are second-most in club history, trailing only Mike Koplove's 15 in 2004.
"Ideally, I want to attack those guys, and I'm trying to get bad contact," Ziegler said. "I pitch to contact most of the time. If I get a chance to strike a guy out, I'll go for it, but I hardly ever start an at-bat thinking, 'I want to strike this guy out.' I'm hoping they hit it on the ground, and hopefully at that point it's at somebody."
Catcher Henry Blanco underwent successful surgery on Wednesday to repair the torn ulnar collateral ligament in his left thumb. The D-backs did not provide a timetable for his return.
Pirates: Locke called up, Presley sent to Triple-A
The Pirates recalled lefty reliever Jeff Locke from Triple-A Indianapolis before Wednesday's game. Locke takes the bullpen spot of Kevin Correia, who started against the D-backs on Wednesday.
"He gives us volume if we need innings," Hurdle said of Locke.
Outfielder Alex Presley was optioned to Indianapolis to make room for Locke on the roster.
The Pirates have gone 24-7 in their last 30 games at PNC Park, and head into Thursday's contest with the best home record in baseball (35-17).
Rodriguez is 3-5 with a 5.40 ERA in eight career starts against the D-backs, but he threw six shutout innings and gave up only two hits the last time he faced them (Aug. 8, 2011).