DENVER -- Jon Gray used to be pretty hard on himself.

“I wish I wouldn’t have beat myself up so bad in the past,” Gray said after the Rangers lost to the Rockies at Coors Field on Friday night, 4-2.

“I should’ve given myself a pat on the back.”

Gray spent the first seven seasons of his Major League career with the Rockies, and a pat on the back just wasn’t in him then. The right-hander was one of Colorado’s best young starting pitchers, but Coors Field, with its altitude and enormous outfield, can chew up and spit out the very best of hurlers.

Overall, Gray posted a 4.59 ERA (107 ERA+) in his time with the Rockies. After he was selected third overall in the 2013 Draft out of the University of Oklahoma and made a rapid rise through Colorado’s farm system, he was seen as having the potential to become the long awaited “ace” of a franchise that had never had one over a sustained period of time.

That potential was never realized in full while Gray was in the Mile High City. But given what he’s been doing for Texas since signing a four-year, $56 million deal following the 2021 season, it seems it’s being realized now.

Gray made his first start at Coors Field as a visitor on Friday night and continued a run that he calls the best of his career by going six innings and yielding one run on eight hits, walking one and striking out seven. That lowered his season ERA to 2.36, and if you take out a rough season debut, he owns a 1.50 ERA across 42 innings.

It’s all clicking now. His slider is sharp and the key to his repertoire; he threw it 56% of the time on Friday against his former club, generating 14 swings and misses. He mixed in his mid-90s fastball, and although he dealt with traffic most of the evening, he escaped trouble time and again.

Standing on the mound, Gray could think back to times on that very spot when he was unable to evade disaster. Unable to explain why he would so often start strong and unravel late, he would sometimes look to the flag poles to the left of the scoreboard to steady himself.

The expectations were heavy and he only added to the weight.

“I think I did overthink things for a lot of years because I always thought I was the problem,” Gray said. “I wasn’t going to forgive myself for making bad pitches. I thought it was lack of effort or just not understanding something.”

What Gray learned from his tenure in Denver was that he wasn’t the problem. It took some time for him to reach that realization, but after he left Colorado, he began the journey.

A major mile marker on that trek was when Gray shifted his mindset in a big way. What was the pivotal change?

“When I stopped caring,” Gray said, “caring about the results.”

That may sound flippant on its face, but it’s not. What Gray meant was that he stopped living and dying with every pitch. Coors stressed that out of him.

“I don’t get nervous at all anymore,” he said. “Never, ever. And I love it. It’s fun. … I feel like everything in front of me is gonna be much easier.”

The new Gray, steeled by Coors Field, is paying off for the Rangers, especially at a time when the rotation has been decimated by injuries. Jacob deGrom and Max Scherzer were already sidelined when Nathan Eovaldi, Dane Dunning and Cody Bradford all hit the injured list within the past month.

“He’s stabilized this rotation with the job he’s doing and how consistent he’s been,” manager Bruce Bochy said. “… He’s been critical for our rotation with how much we’ve had to go through with guys going on the IL.”

Gray sees good things ahead. But it was the tough times, the times when he sat at his locker in the home clubhouse at Coors pondering what went wrong, that paved the way for the success he’s having now.

On Friday night, he returned a different pitcher.

“In terms of attacking hitters, this place has set me up better than any other place,” Gray said. “I think there’s been times of growth these past couple of years and I’m just overall a little better.”

That sounds a lot like a pat on the back.