Brewer started the season for the Hokies but broke his collarbone in the third quarter against Ohio State and missed the next five games. He came on in relief of struggling quarterback Brenden Motley in the second half Saturday against Miami, but Brewer's attempt to rally Virginia Tech fell short.
He was originally expected to miss eight to 10 weeks.
The Hokies face a must-win situation against Duke in the Coastal Division on Saturday. Virginia Tech sits in sixth place at 1-2 in ACC play and cannot afford another loss if it wants to keep pace.
Brewer started every game for the Hokies last season after transferring from Texas Tech and was key to their upset win over Ohio State in 2014.