Major League Baseball's Reliever of the Year award is only 10 years old, with the first awards (AL and NL) being handed out in the 2014 season.
Last season, Devin Williams (National League) and Felix Bautista (American League) took home the award. While Williams didn't lead the NL in saves, he put together quite the season for the Milwaukee Brewers.
With Josh Hader now in the American League, oddsmakers are making Williams the favorite to repeat as the award's winner this seson, but he has some competition. Edwin Diaz, who missed all of last season for the New York Mets, is +350 to win the award, right behind Williams at +300.