PITTSBURGH -- David Freese is adjusting to a part-time role nicely in his first season with the Pittsburgh Pirates.

Freese hit a long two-run home run to cap a four-run fifth inning, Sean Rodriguez also homered and the Pirates rallied for a 5-4 victory over the Arizona Diamondbacks on Wednesday night.

Freese's 451-foot blast into the Pirates' bullpen in center field off Rubby De La Rosa (4-5) put the Pirates ahead 5-4. They trailed 4-1 coming into the fifth, but Gregory Polanco hit an RBI double and Starling Marte drove in a run with a groundout.

The Pirates signed Freese as a free agent in March to fill in at third base while Jung Ho Kang recovered from reconstructive left knee surgery performed last September. Since Kang was activated from the disabled list May 6, Freese's playing time has been limited, but the former World Series MVP with the 2011 St. Louis Cardinals isn't complaining.

"For one thing, you've got to love where you're at and I love it here," Freese said. "I love coming to the yard every day. I love playing on this team. I love being around the guys. That makes it easier to put aside personal playing time."

Rodriguez, subbing for an ill Josh Harrison at second base, hit a solo homer in the fourth. It was Rodriguez's fifth, one more than he had last season.

Polanco stayed hot with three hits. He is batting .343 with 14 RBI in 16 games since being moved to the No. 3 spot in the batting order and also has multiple hits in five of his last eight games. Polanco raised his career batting average against the Diamondbacks to .354 in 18 games.

Andrew McCutchen added two hits while the Pirates won for the eighth time in 10 games overall and 11th time in their last 14 games against the Diamondbacks.

Jeff Locke (3-3) gave up four runs and seven hits in 6 1/3 innings for his first career victory against the Diamondbacks. He walked one and struck out one.

"In my eyes, it's not a very good performance by me," Locke said. "Mistakes were made, mistakes that we're not supposed to make in those situations, but the offense hung tight all night. We battled back."

Mark Melancon worked around Chris Owings' second double of the game with two outs to pitch a scoreless ninth and get his 16th save in 17 opportunities.

De La Rosa, pitching for the first time since May 15, was tagged for five runs and nine hits in 4 1/3 innings. He had his last turn in the rotation skipped because of tightness in his groin and triceps.

"He just tired out," Diamondbacks manager Chip Hale said. "Coming off the layoff we were real cognizant of how many pitches he was going to go. He was going to be right around 100 -- it was his game there in the fifth inning. But he hung a slider and Freese has made us pay numerous times this year."

Freese is 6 for 15 with four doubles and a home run against the Diamondbacks this season.

Yasmany Tomas and Rickie Weeks Jr. both had a home run among two hits for the Diamondbacks.

Weeks started in right field, his first appearance at the position in his 13-year career.

TRAINER'S ROOM

Diamondbacks: 2B Jean Segura and SS Nick Ahmed passed concussion tests and were cleared to play after both were hit in the head by pitches Tuesday night. Ahmed went 1 for 4 but Segura, who is hitting a team-best .316, was held out as a precaution as he still felt some dizziness after Tuesday's game.

Pirates: RHP Arquimedes Caminero (strained right quadriceps) was placed on the 15-day disabled list a day after hitting Segura and Ahmed.

BULLPEN MOVES

The Pirates also placed LHP Tony Watson on the paternity list and recalled LHP Kyle Lobstein and RHP Rob Scahill from Triple-A Indianapolis.

Watson has made 10 consecutive scoreless appearances. Players on the paternity list can miss up to three days.

UMPIRE INJURED

Home plate umpire Chris Guccione left following the first inning after he took a foul tip to the mask off the bat of Freese in the bottom of the inning. Guccione walked off the field under his own power.

First base umpire Sean Barber took over behind the plate. Alfonso Marquez and crew chief Larry Vanover were left to handle the bases.

UP NEXT

Diamondbacks: LHP Patrick Corbin (2-3, 3.99 ERA) will start Thursday in the finale of the three-game series. He has a 2.88 ERA in his last four starts.

Pirates: RHP Gerrit Cole (5-3, 2.79) has won his last three starts with a 1.29 ERA.