WEST PALM BEACH, Fla. -- Astros pitching prospect Hunter Brown grabbed his cell phone and anxiously punched in Justin Verlander’s number. He was extremely nervous calling the phone of his idol growing up, and those nerves didn’t fade even though the voice on the other end of the line was friendly and accommodating.

“He said, 'Just have a good season and do your thing and go out there and pitch,'” Brown said of his recent interaction with the Astros’ ace. “I modeled a lot of my game after Verlander. It’s really cool being on the phone with him.”

The conversation was set up by Astros manager Dusty Baker and former pitching coach Brent Strom, both of whom knew Brown, a Michigan native, was a huge fan of Verlander as a kid. So much so that Brown used to stand in front of the mirror at his grandmother’s house and mimic the two-time Cy Young winner’s windup.

Brown, a fifth-round pick out of Wayne State in 2019, has rocketed into position as the Astros’ top Minor League pitching prospect. He threw his first bullpen session of Minor League camp on the back fields at Ballpark of the Palm Beaches on Thursday, and he was glad to be out of the cold and snow in Michigan and under the warm Florida sun.

Many eyes were on Brown, who worked on his slider a lot this offseason, because that’s the pitch he says has been the most inconsistent.

“That’s just kind of where you want to be, right?” Brown said. “It’s a good feeling, I guess, but you’ve got to go to work and you’ve got to show up and get your work done and take it from there.”

After making huge strides with his curveball during the pandemic shutdown, he made his full-season debut with Double-A Corpus Christi last May and struck out 76 batters in 49 1/3 innings with a 4.20 ERA. He earned a promotion to Triple-A Sugar Land in August and had a 3.88 ERA with 55 strikeouts in 51 innings.

Brown, 23, showed that he could maintain premium velocity in college and continued to do so over a long pro season in 2021, when he still sat in the mid-90s and hit 99 mph with some riding action on his four-seam fastball in September. His biggest weapon remains his curveball, which he throws along with a slider and changeup.

“The stuff is there,” said Eric Niesen, the Astros’ Minor League pitching coordinator, who was the pitching coach at High-A Asheville last season. “I think everyone's pretty aware of that. And it's just becoming more a complete pitcher, understanding the dynamic of when to use something, how to use it, where to throw it, kind of different developments in that stage. I thought he had a great year. I think it's one of those things where a young guy moves quick.”

There’s no question about Brown’s stuff, but he’s still working on a feel for pitching. He doesn't fully trust his changeup or repeat his delivery consistently, though his control did improve during his two months in Triple-A. The Astros love his work ethic, citing the gains he made while pitching off a homemade mound in his backyard during the 2020 layoff.

“I’m trying to throw four-seamers with high velo, good spin,” he said. “Sliders, I’m throwing a harder slider with not as big of a shape and then I have my curveball, which is a big downward pitch that breaks 12-6. And then my changeup, too. I’m trying to get it to sink and sell it like a fastball.”

Brown, who owns an apartment only steps from Comerica Park in downtown Detroit, will likely open the season in the rotation at Triple-A, putting him close to the big leagues. He already has the kind of mental toughness and confidence seen by many pitchers who have been successful in the big leagues -- including one Detroit legend who re-signed with the Astros last year: Verlander.

“I want to get up to the big leagues and help them win some games,” Brown said. “I think I can help them do that. And that's my goal.”