Green, who also won the Yount Award in 2007 as a 20-year-old, batted .336 with 22 home runs and 88 RBIs in 120 games at Triple-A Nashville, re-establishing himself as a prospect after 2008 and 2009 seasons marred by a wrist injury.
Since being called up in late August, Green batted .333 in 11 games entering Wednesday, collecting eight hits in 24 at-bats, including three doubles with one RBI.
Fiers went 13-3 with a 1.86 ERA between Double-A Huntsville and Nashville, and was at his best at the higher level. In two relief appearances and 10 starts with the Sounds, he was 8-0 with a 1.11 ERA.
"It's a great honor. It shows that someone's watching and someone puts value in you," Fiers said. "I'm not going to lie to you, I check the stats. I thought I had a great year. I feel like I deserved it this year and I worked hard for it."
"It's a great award, but this is the ultimate goal, to get here and do well here," said Fiers, 26, who made his Major League debut on Wednesday night, striking out two Rockies and allowing two hits in the ninth inning. "I'd rather be doing that here, winning Pitcher of the Year in the Major Leagues instead of the Minors. But it's a good stepping stone."
The Brewers began naming Minor League players and pitchers of the year in 1999.
Green, 24, is the first prospect to be honored with the player honor twice, though Ben Hendrickson was a two-time Pitcher of the Year in 2002 and 2004.
"It's just as awesome winning it this time as the first time," Green said. "Being up here is even better. The first time was just proving yourself a little bit and this time is just kind of like, 'OK, yeah, I know I can still do it.' So that's always a good feeling to have."