If recent results and the opener of a three-game series are any indication, the Pittsburgh Pirates and visiting Colorado Rockies are evenly matched.

Both have struggled this season.

The Pirates had lost three straight -- including an 18-4 trouncing Sunday while getting swept by the St. Louis Cardinals -- and five of six coming into the series.

The Rockies had lost 10 of 13 before starting a seven-game road trip in Pittsburgh.

Monday's series opener was tight, with the Pirates squeaking out a 2-1 win thanks to an eighth-inning run.

"We manipulated a run -- or manufactured a run, however you want to put it," Pirates manager Derek Shelton said. "And sometimes when you're not going great offensively, things like that can get you going a little bit. ... To be able to win one where we didn't bang the ball, it was important for us."

Pittsburgh third baseman Ke'Bryan Hayes was integral to the victory, going 3-for-3 with an RBI double and a walk. He also scored the winning run in the eighth when he singled, stole second, advanced on a groundout and came home on Yoshi Tsutsugo's infield hit.

Hayes, one of Pittsburgh's cornerstone players, has struggled at times this season. A hotshot on defense, he has seven errors -- more than double his total from last year, when he played 95 games in the field.

He also has gone through lulls on offense, but his batting average is up to .290.

"Just trying to be aggressive early in the count, not swinging at pitches that I don't want to hit and taking my walks whenever they give them, and then whenever they leave something over the plate, making sure that I'm on time to get a swing on it," Hayes told ATT Sportsnet.

Colorado could be without left fielder Kris Bryant again on Tuesday after he was a late scratch on Monday because of back soreness. He spent time on the IL earlier this season because of a back issue.

"It's just OK," Rockies manager Bud Black said. "I think he's still finding his way physically."

In the middle game of the series on Tuesday, Colorado left-hander Kyle Freeland (1-4, 4.85 ERA) is expected to face Pittsburgh right-hander Roansy Contreras (1-0, 3.52).

Contreras is expected to be called up from Triple-A Indianapolis on Tuesday. He made his major league debut with one start last season, and earlier this season he made three relief appearances, striking out 10 in 7 2/3 innings.

During his time at Triple-A in 2022, Contreras produced a 2.66 ERA in five starts.

He has never faced Colorado.

Freeland is coming off a solid outing in a no-decision. He gave up three runs and seven hits with two walks and a season-best eight strikeouts in six innings Wednesday against the San Francisco Giants.

Perhaps the most impressive thing about that start was a newfound aggressiveness.

"I felt like I did a good job of brushing hitters off the plate, using my fastball effectively inside and not letting them be comfortable over the plate," Freeland said. "I let them know that I'm not afraid to come inside, and if I hit you, I hit you."

Black strongly approved, even as Freeland had to work out of some jams.

"He was able to limit the damage," Black said. "He made a lot of big pitches and he worked hard. I thought he pitched outstanding."

Against Pittsburgh, Freeland is 3-2 with a 3.98 ERA in six career starts.

--Field Level Media