DENVER -- Pete Fairbanks had a gripe over his grip on the baseball.

For that, he blamed the humidor at Coors Field.

The Tampa Bay Rays reliever took issue with the variability of the balls Friday after he issued three walks in the ninth inning. That paved the way for Ryan McMahon's walk-off grand slam as the Colorado Rockies rallied for a 10-7 victory in their home opener.

"They were horrible. You can mark that down in all caps for me -- horrible," Fairbanks said of the baseballs. "No excuse, though."

The Rockies installed a humidor room at Coors Field in 2002 to control the moisture level in baseballs, which helps keep them from becoming dried out in Denver's thin air.

It does take some getting used to. The Rays haven't been in the Mile High City for a series since 2016. The team also is coming from sea level.

"There's definitely a difference. It's definitely different," said Rockies pitcher Peter Lambert, who threw two scoreless innings Friday. "Sometimes, it can be a little more dry and the ball can feel a little more chalky, for sure."

Fairbanks started the ninth by walking Jake Cave, Brendan Rodgers and Nolan Jones. In all, the right-hander threw 17 pitches -- five for strikes -- without getting an out. He was replaced by Jason Adam, who struck out Kris Bryant before giving up the grand slam to McMahon.

"That's what happens when you don't throw strikes," said Fairbanks, whose team rallied in the ninth from a four-run deficit to take a 7-6 lead. "You get punished for it. So I'd love to see those come out of the humidor tomorrow in a little better shape before they get rubbed up. But there's nobody to blame but myself for not being able to adjust to some of the quality issues."

Asked if the baseballs were too wet or dry, Fairbanks responded: "They were just overall bad. I'm not going to elaborate further than that.

"They were not uniform from ball to ball. Just dry, smooth, whatever you want to say."