SAN DIEGO -- The worst of the National League West is tying a bow on their four-game series.

The Arizona Diamondbacks (51-72) face San Diego (52-71) on Sunday with the Padres trying to snap a four-series losing streak.

The Padres, who are headed to their sixth straight losing season, took the first two games before the Diamondbacks rallied behind Robbie Ray's gem to win Saturday night.

San Diego will be looking to get more hits than errors Sunday, something they didn't do on Saturday. The Padres had four errors and three hits.

Arizona right-hander Braden Shipley gets the nod and the Diamondbacks are hoping he doesn't repeat his last performance. Shipley, who is making his first career start against the Padres, was rocked for seven runs (six earned) over five innings in losing to the New York Mets on Tuesday.

It was stumble for Shipley, who has been pretty solid since his debut. And he was cruising along through the first four innings when trouble arrived in the fifth. Manager Chip Hale stayed with his youngster and he didn't record an out in the sixth.

"We don't want them to take their lumps to the point where we're out of a game," Hale said. "I wish I could've gotten him out of there a little quicker."

Before the Diamondbacks get out of town, they'll face righty Luis Perdomo. An afterthought at the beginning of the season, Perdomo has become the senior member of the rotation after James Shields, Drew Pomeranz and Andrew Cashner were traded. With opening day starter Tyson Ross limited to one start, Perdomo has been thrust into a more prominent role.

Perdomo, who has hit an uneven patch, is making his 14th career start and second against Arizona. He was tagged with his third straight loss in his last outing Monday against the Tampa Bay Rays.

Although he didn't pitch that bad, He was charged with three runs and five hits over 5 2/3 innings. His trouble came in the early innings when he was trying to be too fine. He tip-toed out of a first-inning bases loaded jam by allowing one run.

"Trying to be too perfect," Perdomo said through a translator. "That was the biggest issue that I had."

Two of Perdomo's wins have come against the Diamondbacks, including one in relief. He prevailed in a start on July 4, when pitching six innings of three-run ball.

It's the first game for the Diamondbacks in which they officially know shortstop Nick Ahmen is out. He'll undergo season-ending hip surgery next week.

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