CLEARWATER, Fla. -- Almost four years after he was the No. 1 overall pick in the draft and 15 months after the Phillies took a shot on him in a trade with the Houston Astros, Mark Appel remains a tantalizing curiosity.
The right-hander's professional career has been defined by unfulfilled potential, but that strong-bodied, 6-foot-5, perfect pitcher's frame and power arm are just too mesmerizing to give up on.
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This is a big season for Appel. He will turn 26 in July, and he's healthy after having surgery to remove a bone spur in his right elbow in June. With that, the Phillies sent him off to minor-league camp on Tuesday. In three weeks, he will embark on the season that he hopes will finally land him in the major leagues.
"Everybody kind of makes their own opportunity based on how they play," Appel said. "So, that's where my focus is. I know if I go out there and do the little things that I've been doing the last eight or nine months since surgery and keep this progression that I've been on, that I'll be there in no time.
"It's just a matter of being able to go out and prove that I'm healthy, prove that I can give the team five, six, seven innings, keep the team in the game. I think that's really where my head is at. It's just a matter of going down to minor-league camp and doing my thing."
It's not out of the question that Appel ends up in the bullpen some day. For now, the Phillies want him to continue to get starter's reps so he can work on his primary flaw -- control. He projects to open the season in the Triple A rotation. He opened there last season and went 3-0 with a 1.64 ERA in his first four starts. He followed that by going 0-3 with an 8.27 ERA in his next four starts before being shut down with the elbow problem. For the season, Appel worked 38 1/3 innings. He struck out 34 but walked 20.
Appel spent a month in big-league camp this spring and pitched in four Grapefruit League games. In nine innings, he gave up seven hits and five runs. He struck out 10 but walked four.
Phillies pitching coach Bob McClure is one of those folks who marvel at Appel's raw talent. He saw progress this spring.
"I'm seeing more quality in his pitches," McClure said. "For me, it looks like he's going forward and that's a big thing. He's not scattering balls all over. His misses are not as frequent and not as bad as they were. I'm very pleased where he's at and he should be too. He's made good progress coming off surgery."
McClure believes Appel will pitch in the big leagues someday. He said the pitcher's goal for 2017 should be to throw "the least amount of pitches per inning as he can."
In other words, fill the strike zone.
Appel knows he needs to improve on that.
"I think I've taken kind of big strides this spring," he said of his control.
He mentioned having some chats with Larry Andersen, who served as a guest pitching instructor early in camp. Andersen stressed the importance of an aggressive mindset and pitching with confidence, two qualities that Appel has not always shown.
"Larry and I had some conversations about the mentality of pitching and really just having confidence and not trying to throw a strike but knowing you're going to throw a strike," Appel said. "There's kind of a difference in knowing it in your head and kind of believing it in every fiber of your body. It makes a difference when you're on the mound."
On the Phillies' depth chart of upper-level pitching prospects, Appel ranks behind Zach Eflin and Jake Thompson, who both made it to the majors last season. He's probably also behind Ben Lively, Nick Pivetta and Ricardo Pinto. Drew Anderson is a pretty hot name, as well.
But Appel still has the physical tools that led the Astros to draft him No. 1 overall in 2013, the tools that continue to make him a tantalizing curiosity, a lottery ticket the Phillies hope to cash in on. It's just that it's getting to be time for him to start making his move.
"I think I've had times when I've been antsy, but there's a lot of patience with me," Appel said. "I think I've experienced a lot of things. I've experienced times of just pitching really poorly, my performance has lacked. I've had times when I've been injured and there have been setbacks -- last year was obviously a big one for me. I think in that sense there's always the hope, and the dream and the goal of getting to the big leagues, but you can't do it overnight. So I think it's just a matter of staying the course, staying the process."