Breakout pitching prospects of 2017

A 4-4 record with a 2.58 ERA at Double-A Pensacola earned Luis Castillo a call-up to Cincinnati in June. David Banks/USA TODAY Sports

Yesterday, we talked about the minor league hitters who have seen the largest projection improvements over the course of the 2017 season.

Now we turn to the pitchers, and some of the lessons with minor league hitters go doubly for the hurlers. Even more than hitters, pitching prospects can turn a corner very quickly. Not all minor league pitchers tear through the minor leagues fully formed.

The "why" to this is a lot harder than the "what," but there's a certain art to pitching at higher levels. A slugger can always hit the ball a long way, but a pitcher who might have dominated high school or college with throwing rather than pitching will tend to have a much harder time against the generally more disciplined hitters you find on the professional level.

This holds true even throughout major league careers -- established MLB pitchers are harder to project than established MLB hitters -- but it's magnified in the minors among the prospect set.

Below are some of the largest breakout 2017s in ZiPS among minor league pitchers, the players with the 2017 seasons that most moved the needle on the projections. We list each player with his respective parent organization.

Chance Adams, New York Yankees
Preseason Projected ERA: 5.32
Current Projected ERA: 4.35

It's not without good cause that the Yankees weren't thrilled about the idea of including Adams in their many trade discussions last month, as Adams continued his tear through the minors. A prospect such as he showing some adeptness at avoiding that mistake pitch has a good shot to succeed in the very homer-friendly MLB we have today.

The Yankees didn't turn to him this year to replace Michael Pineda, but that has more to do with a team in a pennant race being a bit risk-averse than any serious concerns about Adams.