Since enduring a rough start that led to bullpen duty, the only thing that has slowed Rubby De La Rosa down lately has been some minor aches and pains.

After receiving much-needed rest, the right-hander will try to pick up where he left off Wednesday night when the visiting Arizona Diamondbacks look to avoid their 11th loss in the past 14 meetings with the red-hot Pittsburgh Pirates.

De La Rosa (4-4, 3.53 ERA) would rather forget the first couple of weeks when he went 1-3 with an 8.44 ERA in five games, including three relief appearances.

Those struggles now seem like long ago as he's gone 3-1 with a 1.93 ERA in five starts since returning to the rotation. In his last outing, he gave up only a solo home run over 6 2/3 innings in a 2-1 home loss to San Francisco on May 15.

De La Rosa became the 12th pitcher in club history to allow one hit or fewer in six-plus innings and the first since Chase Anderson surrendered one hit over seven in June 2015 before leaving with groin tightness. The Diamondbacks then skipped his last start while he dealt with that injury, along with a blister and tight triceps.

"He had those nagging little injuries," manager Chip Hale told MLB's official website. "It just came down to the situation where Rubby had had that tight triceps, the tight groin. He had the blister thing, which, I think, talking to the training staff, is pretty regular for him. He creates so much friction with the velocity."

The Diamondbacks are concerned about second baseman Jean Segura after he was beaned in Tuesday's 12-1 season-opening loss and sent to the hospital for tests upon showing signs of a concussion.

Segura, who has a team-high .316 average, seems likely to miss some time.

Short-handed Arizona (21-26) hopes avoid its first back-to-back road losses since May 3-5 as it takes on a surging Pittsburgh team that has averaged 6.3 runs and hit .332 through the first eight games of this 10-game stay at PNC Park.

De La Rosa has gone 1-0 with a 1.38 ERA in two starts versus the Pirates (25-19). He gave up one run and three hits over six innings in a 7-1 home win April 23.

Sean Rodriguez homered and John Jaso doubled off him. However, Josh Harrison, Starling Marte and Andrew McCutchen are 0 for 16 lifetime in the matchups.

Gregory Polanco went 3 for 5 with a home run, double and five RBIs Tuesday. He's batting .317 with three homers and 13 RBIs in 15 games since manager Clint Hurdle elevated him to third in the lineup.

"You know you're in the middle of the lineup,'' Polanco said. ''You're expected to hit. You're fighting every pitch, every at-bat.''

The Pirates will give the ball to Jeff Locke (2-3, 5.00) as they go after their eighth win in 10 games. The left-hander is coming off one of his best performances, allowing two runs over seven innings in Thursday's 8-2 home win over Atlanta.

Locke is 0-2 with a 7.88 ERA in three starts against the Diamondbacks, though he hasn't faced them since July 2014. Paul Goldschmidt is 5 for 9 in the matchup.

Phil Gosselin had two of the team's six hits Tuesday when Arizona fell to 2-2 on a six-game road swing.

Pittsburgh's Jordy Mercer is 11 for 23 over his last seven games and 7 for 16 in his past three versus Arizona.