Miller will have surgery today to repair the collarbone, Arkansas confirmed Thursday night in a news release.
The injury is a severe blow for the senior, who had shown signs over the past three weeks that he had recovered from the serious knee injury that ended his 2008 season.
Miller broke his collarbone when he dove for a pass during a team drill early in Thursday's morning practice inside Arkansas' indoor facility. He hit the ground hard and writhed in pain as two athletic trainers and Arkansas coach Bobby Petrino checked on him.
Miller is the third Arkansas player to suffer a serious injury since the Razorbacks opened preseason camp on Aug. 6. Tight end Chris Gragg (dislocated ankle) and cornerback Isaac Madison (torn ACL) will each miss the entire season.
Miller was expected to play a role in Arkansas' offense after showing that he had recovered from the torn anterior cruciate ligament suffered toward the end of last season.
Aside from having to occasionally sit out a practice to rest his surgically repaired knee, Miller appeared to be running at full speed and making plays with the offense.
He led all of Arkansas' wide receivers last season with 490 yards to go along with his 30 catches and two touchdowns
Miller Out 4-6 Weeks With Broken Collarbone
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