ARLINGTON, Texas (AP) — A.J. Pollock hit a three-run homer during a five-run second inning, and the Arizona Diamondbacks beat the Texas Rangers 7-4 Wednesday night to spoil Matt Harrison’s first start in more than a year.

Harrison (0-1) made his previous start on May 13, 2014, against Houston, when he left with back stiffness about a month before career-threatening spinal fusion surgery. It was the last of three procedures for back problems that limited the left-hander to six appearances over two seasons.

Randall Delgado (4-2) was the second of five Arizona relievers behind right-hander Jeremy Hellickson, who came out after four innings because of a blister on his right thumb.

Brad Ziegler pitched a perfect ninth for his career-best 14th save.

Welington Castillo hit a two-run homer for the Diamondbacks.

Arizona improved to .500 (42-42) for the first time since April 24 while handing the Rangers their eighth straight home loss, one shy of the club record since moving to Texas in 1972. It was the team’s fifth straight loss overall.

Harrison, an All-Star in 2012 before back problems surfaced early the next season, was activated from the disabled list Saturday. That was the deadline for the move at the end of a 30-day rehabilitation assignment that included six minor league starts.

He was called for a balk in a scoreless first inning that started with a single by Nick Ahmed, who had two hits along with Pollock and Castillo. Four straight hitters reached with two outs in the second, capped by Pollock’s drive into the seats above the 14-foot wall in left field for his 11th homer.

Harrison, who threw in the mid-90s (mph) before he started having back issues, hit 87 mph with his first fastball, but couldn’t go above that. He walked three and struck out one. There is no known history of a major leaguer coming back from spinal fusion surgery.

The 29-year-old got a standing ovation when he was replaced after allowing Pollock’s leadoff single in the fifth. He gave up six hits and six runs in four innings.

Hellickson allowed six hits and two runs with two walks and four strikeouts, including Robinson Chirinos and Delino DeShields back-to-back with the bases loaded and no outs in the fourth inning and Arizona leading 5-2. Hellickson escaped the jam by getting Shin-Soo Choo on a flyout.

Delgado pitched 1 1-3 scoreless innings, the first of four relievers to shut down the Rangers over the final 3 1-3 innings.

Castillo’s seventh homer, off reliever Anthony Bass, gave Arizona a 7-2 cushion in the fifth. Josh Hamilton’s RBI double in the fifth and Choo’s sacrifice fly in the sixth got the Rangers within three.

TRAINER’S ROOM

Rangers: LHP Martin Perez pitched seven innings in a rehab start for Triple-A Round Rock on Tuesday. He gave up seven hits and two runs with no walks and two strikeouts. His rehab stint can go through July 21, the first time the Rangers will need a fifth starter after the All-Star break.

UP NEXT

Diamondbacks: RHP Chase Anderson (4-2) goes in the opener of a three-game series at the New York Mets on Friday night.

Rangers: LHP Wandy Rodriguez (5-4) starts the opener of a three-game home series against San Diego on Friday after Texas’ second day off this week.