Once deemed the biggest bust in draft history, former No. 1 overall pick Mark Appel is heading to minor league camp with the Philadelphia Phillies, ready to embark on a comeback after last pitching in a game in 2017.

Appel, 29, talked with reporters on Monday from a Florida hotel room, where he waits in quarantine until camp opens later this week. Not counting active minor leaguers, Appel is one of three No. 1 selections who never reached the majors, the others being Steve Chilcott and Brien Taylor. He's ready to chase that dream once again.

"I think that ate at me while I was playing, much more than it's eaten at me since then," Appel said. "I think I've made peace with who I am, what's happened in my life, what's happened in my career and still have a lot of joy about where I'm going. ... I'm here because I'm playing for the love of the game."

Appel's return to baseball actually began in 2018, not long after he had stepped away from the sport for "an indefinite time."

It began at a baseball game. Appel, the No. 1 overall pick in the 2013 draft, went to an Oakland A's game to catch up with his former Stanford roommate, A's outfielder Stephen Piscotty.

"At first I wasn't sure how I'd feel going to a baseball game, feeling pretty beat up and worn out from the game, but I enjoyed it," Appel said. "I realized I still love the game and I don't have any bitterness or resentment or regret towards anything that happened in my career."

One of the most decorated pitchers in NCAA history, the Pirates drafted Appel eighth overall in 2012, but he returned to Stanford for his senior season and the Astros selected him first in 2013, one spot ahead of Kris Bryant. His pro career got off to a rocky start, including a 6.91 ERA across two levels in 2014. He had his best season with the Astros in 2015, posting a 4.37 ERA in 25 starts between Double-A and Triple-A, but the Astros included him in a trade that offseason in which they acquired closer Ken Giles.

He was never right in his two seasons with the Phillies. He made just eight starts in 2016 and was diagnosed with a partially torn labrum and rotator cuff. He attempted to rehab without surgery, but made it through just 17 starts in 2017.

"The last few years I was playing it felt like I was focusing on survival," Appel said. "How do I get through this next start and then get to the next one? It didn't feel good. Every time I would throw it would hurt."

On Feb. 1, 2018, Appel announced he was stepping away from the game. After going to those games to watch his friend play, however, he realized the bug to play had never completely left him. He knew the process began with getting healthy.

"By the end of the 2018 season, I was starting to question what it would take for me to play again," he said. "It seemed clear that I still had the desire and just wanted to figure out how to get healthy, and started seeing some doctors."

He finally had shoulder surgery in October 2018 and has been rehabbing ever since, including several trips to the Driveline Baseball academy outside Seattle. He reached out to the Phillies in November. He has thrown several bullpens getting ready for camp and while he said he's probably behind where most pitchers are at this point, Appel said he has touched 95 mph while probably sitting at 92.

"I'm going in necessarily expecting to be completely dominant and just be able to feel like I did when I was pitching my best games in college and even some good games in pro ball," he said. "It has been three-and-a-half years since I've faced any hitters, so I'm trying to give myself a learning curve to reintroduce myself back into baseball."

While Appel said he would like to start, he will do whatever the Phillies ask of him. His goal right now is merely to keep improving.

"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."