He played in relief of struggling Brenden Motley in the Hokies' 30-20 loss at Miami on Saturday. It was his first action since he broke his left collarbone in Virginia Tech's season-opening loss to No. 1 Ohio State.
The Hokies (3-4, 1-2 Atlantic Coast Conference) host Duke (5-1, 2-0) on Saturday.
Offensive coordinator Scot Loeffler said the time is right to make the change.
Motley had thrown just three passes in his career when he was called on to replace Brewer against the Buckeyes. He acquitted himself nicely despite his inexperience, but struggled against the Hurricanes, throwing two interceptions and losing a fumble.
Brewer played the fourth quarter, throwing for one touchdown and also getting intercepted.
''Over the last couple of weeks, he was able to obtain some practice reps and try to get the glitches out of his shoulder injury,'' Loeffler said of Brewer. ''And I think in the time he's been gone, Motley's done an excellent job. He stumbled Saturday and it's just the right time for Virginia Tech to have Michael as our quarterback.
Brewer started all 13 games for the Hokies last season. When he was hurt against the Buckeyes, the Hokies trailed 21-17 but had just crossed into Ohio State territory. With Motley taking over, the Hokies faded, 42-24.
Brewer was cleared to return to practice in a non-contact capacity a few weeks ago, but was only given medical clearance to get back into game situations last week. Loeffler said he never considered starting the senior.
''I think this week of practice will be essential for him,'' he said. ''Like I said, after having the type of injury that he had, to throw him in the mix right off the get-go was not right, not fair. The fact of the matter is ... Brenden Motley was doing a phenomenal job and has done a phenomenal job being in the situation that he was in.''
Wide receiver Isaiah Ford had clearly developed a good chemistry with Motley. The sophomore leads the Hokies with 32 receptions for 497 yards, and he leads the ACC with seven touchdown receptions, but he said with Virginia Tech struggling to get its season moving in the right direction again, the change to Brewer makes sense.
''We've got to go out and prepare hard just like we do every week,'' Ford said Monday. ''With him being back, maybe he'll give us kind of a boost of confidence if anything. Like I said last week, though, we never lost our swagger.
''But there's just little things that need to be fixed and we need to fix them this week.''
Ford and tight end Bucky Hodges each caught scoring passes from Brewer last season as the Hokies edged the Blue Devils 17-16, but Duke arrives this season with some of the best defensive numbers in the country.
Duke ranks fourth in total defense, and second in pass defense, allowing less than 145 yards per game.
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