This story was excerpted from Martín Gallegos’ A’s Beat newsletter. To read the full newsletter, click here. And subscribe to get it regularly in your inbox.

OAKLAND, Calif. -- Adapting to a new environment, Kyle Muller entered Spring Training just hoping he could perform well enough to earn a spot in the A’s rotation. So when he stepped into manager Mark Kotsay's office last week, never could he have fathomed the news that was about to drop on him.

“I’m going to be honest, I kind of forgot the whole first half of his speech,” Muller said. “I said, ‘[Expletive], no way!’ I was super excited. I got up and gave everybody a hug. I was smiling from ear to ear the rest of the way.”

In that meeting, not only did Muller learn he would begin the season in the rotation. Kotsay informed Oakland’s No. 5 prospect that he will be making his first career Opening Day start on March 30 against the Angels, making the 24-year-old lefty the lone rookie in MLB to start on Opening Day this season.

“It really means a lot,” Muller said of the Opening Day nod. “It’s something everybody dreams of growing up. … It’s not something I had expected. [But] it was something I had hoped for. I couldn’t be happier.”

Muller joined the A’s from the Braves as part of the return for catcher Sean Murphy this offseason. Rated Atlanta’s No. 1 prospect at the time of the deal, he impressed Oakland’s coaching staff throughout Spring Training with a repertoire that includes a fastball that sat around 93-96 mph and revamped power slider that has led to more swing-and-misses than it had in the past.

Given Muller’s track record throughout the Minors -- he holds a 3.18 ERA in 108 games (107 starts), including 588 strikeouts over 541 innings -- the A’s felt comfortable kicking off the 2023 season by handing the ball to a rookie with 12 Major League games under his belt, the least amount of big league experience for an A’s Opening Day starter since 2014, when Sonny Gray started the season opener with 12 Major League games on his resume. 

“Kyle, in our mind, is going to be in this rotation for a long time,” Kotsay said. “He’s put his work in to get to this point. We’re excited about his future. … When I told him he was going to be the Opening Day starter, his excitement and energy and just drive of emotion were exactly what you want when you tell a guy.”

Adding to the specialness of Muller’s Opening Day honor is that Shea Langeliers will be the catcher behind the plate. Rooming together in Arizona for Spring Training, the two came up as top prospects in the Braves organization, often visualizing what it might be like playing in the big leagues together. The root of their relationship, however, predates pro ball.

Muller and Langeliers became acquainted with one another as Texas high school baseball standouts. In 2016, Muller was named Texas Division 6A Player of the Year and Gatorade National Player of the Year for his two-way dominance as a pitcher/outfielder at Jesuit College Prep in Dallas. That same year, Langeliers made First Team All-State. Funny enough, he made the team as a reliever, starring as a lights out closer for Keller High, which is about 30 minutes west of Jesuit.

“Just two Texas kids out there playing baseball,” Langeliers said. “I’m super excited. Just happy for [Kyle].”

“[Shea] was the first person I told because they told me not to tell anybody else,” Muller said. “We were like little kids, man. We were jumping up and down talking about it. It’s going to be cool.”

It’s not quite as significant as a Major League debut, but Muller expects to feel similar nerves. His parents and sister will fly to Oakland to be on hand. His brother, Chris, is a Minor League pitcher with the Rays and is unable to attend.

Also not lost on Muller is the star power of this matchup. Taking the mound for the Angels on Thursday night: Two-way superstar Shohei Ohtani.

“That’s the No. 1 player in the world,” Muller said of Ohtani. “My first start was against [Jacob] deGrom. That was freaking cool, too. As a baseball fan, looking at it now, it’s cool. But once we get out there on Thursday, we’re going to forget about all that and try to win the game."