During the offseason, Robbie Ray adopted a new diet and workout regimen, yielding lost weight and increased strength. He tweaked his mechanics, shortening his arm action.

He was described as being maniacally disciplined during the COVID-19 layoff as he kept up his throwing routine, and when he reported to Summer Camp, he told manager Torey Lovullo he could pitch in a regular-season game right then.

Ray is still positive that the changes will pay off for him, but as he discovered Saturday night, it’s still a work in progress, as he lasted just 3 2/3 innings while the D-backs fell to the Padres at Petco Park for the second time in as many games to start the season, this time by a 5-1 margin.

• Box score

“Obviously it’s disappointing,” Ray said. “But there’s definitely some positives to take out of it.”

Ray (0-1) retired the first eight Padres he faced and took a 1-0 lead into the bottom of the fourth. He racked up seven strikeouts but also 97 pitches, and he didn’t survive the Padres’ first big rally.

Wil Myers delivered the big hit in the fourth, sending a Ray pitch into the bleachers in left for a three-run homer. Three batters later, Ray was gone.

“I thought he got off to a really good start, and he was attacking the zone and gave us a chance to take the lead,” D-backs manager Torey Lovullo said. “And I think in the third and fourth innings, it just built up on him. Too many three-ball counts, not attacking the zone, not finishing off hitters when he had the opportunity to. It was just two consecutive innings that were very long and grinding on him. I think, in those two innings, he lacked consistency and the repeatability that we’d seen from him in Summer Camp.”

Ray’s teammates raved about how he looked in Summer Camp, much as they did during Spring Training.

Saturday marked the first time he had pitched against an opponent in an empty ballpark with only simulated crowd noise over the sound system and cardboard cutouts in the seats.

“I honestly think it was just like the first start of any year,” he said. “I had the same kind of adrenaline and needed to control it a little bit better. I was just kind of getting under the ball -- fastballs were riding up and away from me. I was falling behind in some counts, I was getting away with it because I felt like my stuff was really good tonight when it was in the zone. That’s something to take away from it -- when I was in the zone, it was really good.”

Ray’s stuff has always been good. A fastball that can reach the mid-90s, a sharp slider and a curve for a change of pace.

“He's just one of the filthiest guys in the league,” Padres manager Jayce Tingler said. “He piled up some punchouts early, but I thought our guys did a good job of making him work. We fouled some pitches off, really couldn't square him up early in the game. But to foul some pitches off, lay off pitches outside the zone, get his pitch count up, I thought that was important.”

And that’s where Ray can find himself in trouble. The pitches begin to add up, and before you know it, he’s out of the game before the fifth inning. The revised mechanics, he believes will help his command and allow him to pitch deeper into games.

But he’s still getting fully comfortable with them and learning what his keys are so that he can make the corrections in the heat of a game.

“With the new delivery, I’m still trying to figure out how to slow things down,” he said. “It feels real comfortable. I’m just getting quick, and I’ve got to take a step back and I’ve got to slow things down.”