Sordell (knee) and Varney (glutes) were withdrawn with injuries during the first half of the 1-0 win over Nottingham Forest last weekend, with Varney being replaced by Lucas Akins after himself replacing Sordell.
Both players are rated a 50/50 chance for Saturday but Brewers boss Nigel Clough has options in the shape of Akins, Cauley Woodrow and Chris O'Grady.
Midfielder Lee Williamson and defender Damien McCrory have been overlooked recently but will hope to return to the squad if there are any injury absences.
Defensive player Alan McCormack returns to the Brentford squad after a spell out injured as the Bees look for a response to their loss to Wolves.
He played for 45 minutes in a B team game in midweek and boss Dean Smith is happy enough with his fitness to include him in the travelling party.
Defender Andreas Bjelland has returned to training, but the trip to Burton will come to soon for him.
Midfielder Josh McEachran has suffered an injury setback with a scan on the ankle injury he suffered in February confirming ligament damage.