Mark Appel has no expectations, other than improvement.

He left baseball in January 2018, following five seasons' worth of struggles in the Minor Leagues with the Astros and Phillies. He suffered from injuries and the burdens of expectations after Houston made him the first-overall pick in the 2013 MLB Draft. Baseball stopped being fun along the way and Appel knew he did not want to pitch through the pain in his right shoulder any more. But only months after he walked away, he found himself thinking about coming back.

Appel, 29, is coming back. He is in Clearwater, Fla., where he plans to resume his baseball career. And maybe, if things break right, he might finally make the big leagues. Appel is one of only three first-overall picks in baseball history not to make the big leagues (not including active minor leaguers). Brien Taylor (Yankees, 1991) and Steven Chilcott (Mets, 1966) are the others.

“I would say that ate at me while I was playing much more than it’s ever eaten at me since then,” Appel said on Monday afternoon in a Zoom call with reporters. “I’ve made peace with who I am, what’s happened in my life, what’s happened in my career. I still have a lot of joy about where I’m going and what I’m doing.

“Being able to play baseball, the time and age component, it’s a huge factor in baseball, for whatever reason. It’s always the youngest player to do this, the youngest player to do that, how quickly your service time, all these things. And for me, all those things have gone out the window. Yeah, those things are like, totally irrelevant at this point. I'm here because I'm playing for the love of the game.”

Appel watched his good friend, Stephen Piscotty, play for the A’s at Minute Maid Park in Houston in the summer of 2018. Appel was not sure how he would feel going to a baseball game, but he enjoyed it.

Then, he started thinking about getting healthy. Appel had not been healthy for a long time. Houston selected him with the No. 1 pick in 2013, one pick ahead of Kris Bryant and in a first round that included Aaron Judge, Tim Anderson and Jon Gray. Appel had a 6.91 ERA in his first full season in professional baseball in 2014. He had a 4.37 ERA in 25 starts between Double-A and Triple-A in ‘15. The Astros lost faith in him. They dealt him to the Phillies in December 2015 in a multiplayer trade for Ken Giles.

Appel fared no better with the Phillies, pushing himself through elbow and shoulder pain so he could live up to the hype. He had a 5.01 ERA in two seasons with Triple-A Lehigh Valley. He had bone-spur surgery in 2016 and suffered from right-shoulder inflammation in ‘17. The right-hander continued to feel shoulder pain leading into Spring Training in ‘18. He had no desire to pitch through it or go through a lengthy rehab. So he left.

The time away changed Appel’s perspective. He had right shoulder surgery in October 2018. He started throwing again. He visited Driveline outside Seattle. There were some rumblings that he might make a comeback, but he needed more time. This past November, Appel finally called Phillies assistant general manager Ned Rice. They agreed to talk again in January.

Appel’s desire to pitch did not fade.

“I know I wouldn’t be able to be here if I hadn't been able to have a good signing bonus,” Appel said, referring to the $6.35 million he received from Houston. “Because going 3 1/2 years without much of a salary and doing all the rehab and investing money in your health, a lot of guys don't have that luxury. I feel really thankful that I’m even able to be here. Because it is something that I love. And it is something that I'm doing because I love it. And I'm thankful that I'm able to do it. I don't take that for granted.”

So what are Appel’s expectations this season? Improve? Pitch in Triple-A? Pitch in the big leagues?

“I see the 2021 season as a win for me, if I’m able to play, if I’m able to be intentional and focus, and not necessarily focus on trying to recover and trying to stay healthy -- that survival mode,” Appel said on Monday. “Even if I don’t make it to the big leagues this year, that’s kind of how I’m approaching it. Now, could I make it to the big leagues, if things are going great? Obviously, once you're back in the system anything can happen. But I’m not [thinking this season will only be a] success, if I’m in Triple-A or I’m in the big leagues. I want to feel like I’m getting better again. It’s been a long time since I've felt that.”