PHILADELPHIA -- Mark Appel could have wept.

He had so many thoughts running through his mind as he walked off the mound in the ninth inning Wednesday night at Citizens Bank Park. Nine long years, pressures, expectations, injuries, walking away, coming back, not knowing what it might lead to, but knowing he would be at peace and happy with whatever came next.

“Having perspective and remembering even just two, three years ago,” Appel said after pitching a scoreless inning in his big league debut in a 4-1 loss to the Braves. “Even if I was just trying to come back, it’s never been a straight line for me. Even in that whole process, I was lost. I felt like there were times when I was hopeless, that this dream would never happen. So yeah, I was choking back tears.”

Appel is the oldest first overall pick in baseball history to make his Major League debut, at 30 years, 349 days old. The Astros selected him with the top pick in the 2013 MLB Draft. He struggled along the way. He battled injuries. He was traded from Houston to Philadelphia in ‘15. He was designated for assignment in ‘17. He quit in ‘18. He knew then that he might never return. But a few months later he had surgery on his right shoulder in case he changed his mind.

He did. Appel returned in 2021, but he struggled with Double-A Reading and Triple-A Lehigh Valley. Yet he came back for another year, this time as a reliever. He was 5-0 with a 1.61 ERA in 19 appearances with the IronPigs.

The Phillies promoted Appel on Saturday. Of course, his flight from Newark, N.J., to San Diego was canceled. He hopped on another flight from Newark to San Diego, but with a layover in San Francisco.

But what’s one canceled flight and one layover when you’ve waited so long for a moment?

“This whole year has been so special for me,” Appel said. “I was coming in, trying to figure out, where do I fit? What’s my role going to be? The fact I got to go to Lehigh and learn how to be a reliever and have some success. That was fuel to my fire. I didn’t need a callup for it to be a successful year. In that sense, this is all just extra. I’m just really thankful for it. And I’m glad that I’m able to go out and do my best and get to face the world champions from last year. It’s pretty surreal.”

Appel started to loosen up after Jeurys Familia pitched the top of the eighth. His heart raced. Adrenaline flowed. He fired a couple balls to the backstop in the bullpen.

“He let a couple balls eat,” Phillies right-hander Corey Knebel said. “We could tell in the bullpen. Man, it was kind of hard. I didn’t know how hard he threw. The last time I saw him was 2013. I didn’t know what to expect. But that was a very special moment. I know he’s had a long journey.”

Appel calmed down for his final few warmup tosses. He turned, walked down the bullpen steps and walked onto the field.

“I was just trying to compose myself,” Appel said. “You just know the magnitude. Oh, it’s your big league debut.”

Appel jogged to the mound. He took a quick look around the ballpark. He soaked in the moment.

“The music’s louder, the lights are brighter, the fans in Philadelphia are incredible,” Appel said. “I heard people just cheering for me and supporting me, kind of knowing a little bit of my story and the background. It was just a really special moment.”

Marcell Ozuna hit a first-pitch 97.2 mph sinker on a line to Rhys Hoskins, who caught it for the first out.

“It was just really cool to see it all culminate, him running in from the bullpen,” Hoskins said. “I kind of snuck a peek at him a little before second base. Just a grin, right? You just can’t keep it in.”

William Contreras singled after Ozuna, but Appel struck out Adam Duvall looking on a 1-2 sinker. He got Phil Gosselin to ground into a forceout to shortstop Didi Gregorius to end the inning. Appel walked off the field and reached the dugout. Phillies interim manager Rob Thomson congratulated him first. His teammates followed.

Appel was one of only three first-overall picks in baseball history who signed with their selecting team and did not make the big leagues, not including more recent picks who remain active. Brien Taylor (Yankees, 1991) and Steven Chilcott (Mets, 1966) were the others.

“It almost felt like I was being brought into this fraternity of Major League Baseball players,” Appel said.