ARLINGTON, Texas -- Thanks to a knack for two-out hits, the Arizona Diamondbacks are back at .500 for the first time since April 24.

The Diamondbacks scored all of their runs with two outs to beat the Texas Rangers 7-4 Wednesday, completing a sweep of the two-game interleague series and ruining the return to the mound of Texas starter Matt Harrison.

"I don't know if we're changing anything," said Arizona center fielder A.J. Pollack, who had the game's first big blow, a three-run homer in the second inning. "We've just had a couple of breaks, just kept playing hard, and things have worked out a little better.

"We didn't feel we were a losing team. I think our expectations of ourselves are very high, and it's well above .500."

Pollock's blast capped a five-run second inning against Harrison, who was making his first big-league start since last May because of a back issue that led to spinal fusion surgery.

The homer followed RBI singles from second baseman Cliff Pennington and shortstop Nick Ahmed.

Catcher Welington Castillo homered off Texas reliever Anthony Bass in the fifth inning after Pollock opened the inning with a single off Harrison. Castillo did that despite experiencing arm cramps because of dehydration.

Arizona reliever Randall Delgado (4-2) was the beneficiary of the offense. He picked up the win in relief of Jeremy Hellickson, who only lasted four innings and allowed two runs on six hits. Hellickson left with a blister on his right thumb. Arizona manager Chip Hale said he expects the right-hander to be able to make his next start after the All-Star break.

Diamondbacks closer Brad Ziegler pitched a perfect ninth inning for his 14th save.

Harrison was charged with six runs on six hits in four-plus innings. He walked three and struck out one.

"I definitely had some nerves," Harrison said. "It calmed down after the first inning. The second inning is what killed me. I just didn't make the pitches when I needed to. I left some off-speed pitches up in the zone, and they made me pay for it. I got better after that. I threw a lot of pitches and was behind in a lot of counts, so it ruined my night."

Texas, which lost its fifth straight overall and its eighth straight at home, missed out on several chances to score and left 11 runners on base.

"To leave 11 has really not been the characteristic of this club, especially during the stretch when we were going well," Texas manager Jeff Banister said. "I felt like tonight there were some at-bats that got away from us."

Pollack went 2-for-4 with three RBIs and two runs. Castillo and Ahmed each had two hits for Arizona.

Like Pollack, Hale is pleased to see his team get to .500. He also knows the Diamondbacks have more in the tank.

"It is important to get to .500," Hale said. "It's important to get into second place, like we are (tied with the San Francisco Giants), but it doesn't matter till the end of the year."

Texas third baseman Adrian Beltre went 3-for-4 and scored a run. First baseman Prince Fielder added two hits, and right fielder Shin-Soo Choo had two RBIs.

After Arizona's early five-run inning, the Rangers trimmed the lead to 5-2 with two runs in the third against Hellickson, but he escaped a bases-loaded, no-out situation an inning later without allowing a run.

The Diamondbacks restored the margin in the fifth on a two-run homer to right by Castillo.

The Rangers answered with a run in the bottom of the fifth on an RBI double by left fielder Josh Hamilton. Choo's sixth-inning sacrifice fly capped the scoring.

NOTES: Texas 1B Prince Fielder was selected for Monday's Home Run Derby in Cincinnati. It will be the third time Fielder participates in the event. He won the championship in 2009 and 2012. ... Rangers LHP Martin Perez is expected to make another rehab start Sunday, and he could be ready to join the Texas rotation after the All-Star break. Perez has made five rehab starts this year in his recovery from Tommy John surgery. The Rangers won't need a fifth starter again until July 21. ... Texas LHP Derek Holland (shoulder) is slated to throw another bullpen session Friday. The plan was for him to throw Thursday, but it was moved back because the club has an off day. ... Arizona LHP Oliver Perez retired Fielder on Tuesday night, which dropped left-handed hitters to 3-for-27 this season against the former starter.