Khris Middleton is expected to miss more than six months and will undergo surgery to fix a torn hamstring suffered in preseason workouts.
Middleton, who led the Bucks a year ago with 18.2 points per game, tore his hamstring Wednesday and will miss at least six months following surgery.
Just when it looked like the stars where finally lining up for the Milwaukee Bucks, they are dealt with a potentially devastating injury.
Middleton was originally a second-round draft choice by the Detroit Pistons in 2012 out of Texas A&M.
Entering his ninth National Basketball Association season, Beasley has career averages of 13.0 points and 4.8 rebounds while shooting 45.2 percent from the field.
Milwaukee also re-signed veteran forward Steve Novak, a 3-point specialist, in the offseason.
The loss of Middleton is a major blow for the Bucks, a team that has their sights set on returning to the playoffs. Vaughn, who played one season at UNLV before turning pro, averaged 14.3 minutes per contest in 70 games played last season.
Chosen as the 15th overall pick in the 2013 NBA Draft, the versatile forward averaged 16.9 points, 7.7 rebounds, 4.3 assists, 1.4 blocks and 35.3 minutes per game last season.
The Bucks will still have one of the more interesting backcourts in the National Basketball Association, if only because of who head coach Jason Kidd wants to play at the point.
Ennis might have struggled for playing time in Milwaukee this season after the Bucks acquired playmaker Matthew Dellavedova in the off-season, and with Carter-Williams and Giannis Antetokounmpo also serving as primary ball handlers.
Middleton was expected to be part of the core, along with Giannis Antetokounmpo and Jabari Parker, to the lead the Bucks into playoff contention. For his career, the 6-10 Beasley averages 13 points, 4.8 rebounds and 1.3 assists per game.