During his time in the Fall League, Hader has been used exclusively in relief after being both a starter and a reliever in the Minors. He has struck out 15 batters in 10 innings of work while only allowing four hits and four walks with a 0.90 ERA and a .118 opposing batting average in five appearances.
MLB Pipeline ranks Hader as the 14th-best prospect in the Brewers' system.
Among all Fall League pitchers, Hader is third in ERA, fourth in strikeouts and fifth in WHIP at 0.80.
"It's been a good time," the 21-year old said of his first time in the Fall League. "Just kind of refining my mechanics and all of my pitches. Just definitely just trying to stay healthy and finish strong."
Hader has been traded twice in his young career. He was the centerpiece of the deal that sent Bud Norris to the Orioles at the 2013 Trade Deadline and gave the Astros Hader, L.J. Hoes and a 2014 Competitive Balance pick. While he was in Houston's system, he was named the 2014 California League Pitcher of the Year for the Lancaster JetHawks.
In July of this year, Hader was part of another major Trade Deadline acquisition, the deal that brought Carlos Gomez and Mike Fiers to the Astros and sent Hader, Domingo Santana and Hader's Surprise teammates Adrian Houser and Brett Phillips to the Brewers.
"It's been pretty good," Hader said. "The second trade I kind of knew what to expect and how to go about my business and fit in with the new club."
The southpaw wasn't looked at too much out of Old Mill High School in Maryland, but he got a shot from his hometown team, the Baltimore Orioles, who took him in the 19th round of the 2012 Draft.
"It was definitely an honor just to get a chance to even come into pro ball," Hader said. "Just them giving me the chance and kind of just running away with it doing what I can do and just keep working hard to make it into the big leagues."
Hader spent the past year splitting time between two Double-A squads, the Corpus Christi Hooks in the Astros system and the Biloxi Shuckers, the Brewers Double-A affiliate. Across the two clubs, Hader went 4-7 and notched one save with a 3.03 ERA in 24 appearances. Seventeen of those games were starts, including all seven of his appearances for Biloxi. He pitched 104 total innings and allowed eight home runs while striking out 119 and holding opponents to a .224 batting average.
Hader has seen his velocity jump since he was drafted, according to MLB Pipeline. He has touched up to 96 mph at times on his fastball. He said to keep climbing the ladder in the Minor Leagues and make it to Majors, there are still some things he will need to improve upon.
"I just need to refine my off-speed pitches to make them have a good command and to just continue in the same arm slot with them," Hader said.
Kris Vossmer is a senior journalism student at Arizona State University. This story is part of a partnership between MLB.com and ASU's Walter Cronkite School of Journalism and Mass Communication. This story was not subject to the approval of Major League Baseball or its clubs.