News came out Friday that Mark Appel, the Astros No. 1 overall pick in the 2013 draft, has been sent down from High-A Lancaster to extended spring training.

Huge news; Mark Appel is being sent back to extended spring training. Luhnow says he’s not injured. — Jose de Jesus Ortiz (@OrtizKicks) April 25, 2014

General manager Jeff Luhnow called Appel’s 2014 performance so far “unsettling” and he is correct. In four starts totaling just 13 innings pitched, Appel has posted a 6.23 ERA allowing 17 hits, nine earned runs, four walks, two home runs and has struck out 13 batters. According to Baseball-Reference, Appel, 22, is just 1.3 years younger than the median age of all players in High-A.

Photo Credit: @QCBanditPhotog

These results certainly are “unsettling”, especially when compared to other recent top pitching prospects. Jon Gray, who many considered to be the top overall prospect in the 2013 draft, was chosen by the Rockies just two picks after the Astros selected Appel. In his brief four-start stint at Class-A, Gray was significantly more succesful than Appel.

Jon Gray in High-A: 24 IP, 10 H, 2 ER, 6 BB, 36 SO, 0.75 ERA. Mark Appel in High-A: 13 IP, 17 H, 9 ER, 4 BB, 13 SO, 6.23 ERA. — Tyler Stafford (@JeffBlogwell) April 25, 2014

In his most recent start for the Tulsa Drillers, the Rockies Double-A affiliate, all Gray did was carry a perfect game into the sixth inning.

Similarly, Michael Wacha — drafted 19th overall in the 2012 draft, spent just 106 innings in the minors before the Cardinals called him to the majors where he has a 2.57 ERA in just under 100 big league innings. A year after being drafted out of college — the same place Appel is in now — Wacha was in Triple-A, posting a 2.65 ERA.

Obviously, these are shining examples of what pitching prospects can do. Appel was not expected to be in Triple-A by the team at this point in his development, but with his talent and draft status, it certainly was not out of the question.

Appel is clearly extremely talented. So talented, he was pegged as the best draft prospect twice — falling to eighth overall to the Pirates in 2012 and going first overall to the Astros. It is very disconcerting that Appel is struggling this low in the minors, but it doesn’t mean that he is done or ins’t still a very highly regarded prospect.

Remember, Appel missed almost all of Spring Training after having an emergency appendectomy this offseason. The Astros obviously thought that Appel was ready for the season, but maybe he is simply recovering from the surgery and doesn’t quite have his stamina back.

Appel’s setback does raise questions about the Astros use of tandem pitching in the minors. Essentially, the Astros affiliates have eight “starting” pitchers who are paired with another player to pitch no more than five innings every fourth day, according to farm director Quinton McCracken.

Some pitchers, specifically Mike Foltynewicz, are critical of the system. In an interview this Spring Training with the Houston Chronicle’s Evan Drellich, Folty blamed the system for some elbow soreness last season.

“My whole life has been on a five day rotation and that’s all it was, that’s all it’s been,” Foltynewicz said. “Throwing in a piggy-back system and throwing one more day of rest, I couldn’t tell you what the issue was, but I definitely was a little sore.

The tandem pitching system is not unheard of, but it is definitely rare. Folty would go on to tell Drellich he was feeling fine now, but he and Appel are not high-water marks for the Astros new wave process.

Personally, I like the system 95% of the time. It gives the Astros a chance to look at pitchers who might have been cast off as relievers, and the team believes it cut down on injuries to their young arms.

However, when you have a pitcher with the kind of talent and expectations set on him such as Foltynewicz or Appel, perhaps it would be wise to allow them to throw as they would in the majors — going for as long as they can every fifth day.

Even that suggestion is different from what these pitchers experienced in high school and college — taking the mound every Friday and throwing upwards of 100 pitches every time.

There is probably no right or wrong system for pitching prospects within an organization, but the Astros would be wise to listen to their players. If Appel tells them he is uncomfortable throwing every fourth day, don’t make him throw every fourth day. You picked him at 1.1 and gave him a $6.25 million signing bonus for a reason.