The Chicago Cubs possess first-hand knowledge of why Arizona Diamondbacks right-hander Zac Gallen has been one of the majors' best pitchers so far this season.

Looking to help the visiting Diamondbacks avoid a seventh straight defeat, Gallen aims to remain successful when facing the Cubs for a second time in less than a week on Thursday night.

Gallen (2-0, 1.05 ERA) has allowed just four runs on 18 hits and five walks with 35 strikeouts in 34 1/3 innings spanning six starts. He yielded only Yan Gomes' tying solo homer and one other hit while fanning a season-high nine over six innings against Chicago on Saturday.

"How he goes about it, just the look -- he has all of that," bench coach Jeff Banister said, according to the Diamondbacks' website. "There's a lot of precision to (his stuff). There's a lot of swagger, a lot of confidence with it."

However, in the Saturday game, Gallen's Arizona teammates provided him with only one run, and the Cubs scored three times in the ninth off closer Mark Melancon for a 4-2 victory. In four of Gallen's six 2022 starts, the Diamondbacks have scored one or no runs while the righty was still in the game.

The Saturday setback began a Diamondbacks' losing streak that reached a season-high six in a row with a 5-3 road loss to the Los Angeles Dodgers on Thursday. Arizona, which was three games over .500 prior to the Saturday loss to the Cubs, has lost by one or two runs five times during the six-game skid.

"You have to be locked in, you can't make mistakes and you have to go out there and concentrate -- be prepared for every pitch," Arizona third baseman Josh Rojas said.

Though the Cubs essentially were stymied by Gallen, their late-inning breakout in that contest kicked off a season-high string of four consecutive victories, a surge that ended with a 3-2 loss to the Pittsburgh Pirates on Wednesday.

Still, the Cubs have won three consecutive series and should get an added boost with Marcus Stroman (1-3, 5.13 ERA) slated to be activated off the COVID-19 injury list and take the mound for the opener of the four-game set against Arizona.

Stroman hasn't pitched since May 1, when he allowed two hits and struck out five with one walk over seven innings of a 2-0 road victory over the Milwaukee Brewers. The right-hander allowed a total of 13 runs (12 earned) and 14 hits in a two-start span, at Colorado on April 15 and vs. Tampa Bay on April 20. However, he yielded just three runs (two earned) while giving up only eight hits through 13 innings in his past two outings.

"We've missed him, that's for sure," Cubs manager David Ross said. "It will be nice to get him back. He was throwing the ball as good as anyone before he went down."

Stroman is 2-1 with a 3.81 ERA in four career starts against the Diamondbacks.

Arizona's David Peralta is batting just .202 this year, but he is 3-for-6 with a homer lifetime against Stroman. Teammate Daulton Varsho is batting .375 (9-for-24) with three doubles, two homers and eight RBIs in his past six games against Chicago.

Meanwhile, the Cubs' Ian Happ is hitting .323 (10-for-31) in the past nine games overall, and Frank Schwindel is batting .321 (9-for-28) with five RBIs in his past seven.

--Field Level Media