HOUSTON -- Even at 37 years old and coming off perhaps his best season, Astros pitcher Justin Verlander is constantly tweaking his mechanics. The goal is to play until he’s 45 years old or even longer.

The long layoff caused by the COVID-19 pandemic not only allowed Verlander to heal completely from March groin surgery that would have cost him the first two months of the regular season, but it allowed him to dig deeper into his mechanics and make some adjustments that have him feeling “fantastic.”

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That was his assessment after throwing three scoreless, hitless innings Thursday against the Astros’ stacked lineup in an intrasquad game at Minute Maid Park.

“I really couldn’t have scripted a better day than today,” said Verlander, who threw 44 pitches. “I tried to make today as realistic as possible, what we’re going to be like in the season.”

Verlander went 21-6 with a 2.58 ERA last year with a career-high 300 strikeouts in 223 innings while leading the Majors in opponents’ batting average (.172) and WHIP (0.80). He threw his third no-hitter and won the American League Cy Young Award for the second time.

The 12th Opening Day nod of Verlander’s career appeared lost when he went down with a groin injury in early March and wound up having surgery that was set to keep him out six to eight weeks. Then came COVID-19, which provided time for Verlander to heal and reassess. Now he is likely to be the Opening Day starter when the Astros face the Mariners on July 24.

“Obviously, it was horrible circumstances, but it gave me a chance to hit the reset button,” he said.

Verlander experienced groin discomfort in the offseason and felt it had exacerbated when spring camp started. As a result, he ended up straining his lat muscle because he was changing his mechanics to compensate for his groin injury. While rehabbing his groin, he felt it pop, which concerned him enough to seek a second opinion, which led to groin surgery.

Dr. William Meyers, who performed the surgery, told Verlander his groin had scar tissue for a while. A lightbulb went off. Verlander knew he needed to tweak his mechanics to avoid further injury, and he had enough time to do it with baseball shut down.

“One of my goals was to get my mechanics back to what they had been and get my velocity up to what it used to be, or better than last year, anyway,” Verlander said. “I looked at this as an opportunity to get better. I went through a full rebuild process, working on getting my mechanics where I wanted them. I went down the rabbit hole.”

Verlander said his mechanics last year weren’t sustainable over a long period without leading to more injury. He said his delivery last year was “extremely high and vertical and arched” and said his release point was 7 feet, 2 inches off the ground at one point. He wanted to get back to a release point of 6 feet, 5 inches, which is where he was a few years ago.

“That’s a huge difference in height,” Verlander said. “That’s where it started, and that’s what I intended to fix. And, like I said, a bunch of other things, which I was anticipating, popped up along the way, and I just kind of dealt with them along the way.

“I’m not perfect or exactly where I want to be yet, but very, very close. But today was a huge success for me, in my opinion, in just the way it felt.”