Sheffield United striker Jamie Murphy has been ruled out of Saturday's home game through injury.
Murphy was forced out of last week's heavy defeat at Stevenage and is struggling with back and hamstring problems.
Teenager Callum McFadzean replaced Murphy and could be in line for his first league start for the Blades, but on-loan pair Jonathan Forte and Dominic Poleon provide manager Danny Wilson with further options.
Wilson has no other new injury or suspension worries, but could be tempted to make one or two changes.
Defender Danny Higginbotham and forward Chris Porter, back from his loan spell at Shrewsbury, are pushing for recalls.
Teenage striker Diego De Girolamo and defender Lecsinel Jean-Francois have both had surgery to repair cruciate ligament damage and will miss the rest of the season.
The Blades are hoping to climb back into an automatic promotion spot with victory over the second-placed Bees.
Kevin O'Connor and Farid El Alagui are close to returning to the Brentford squad ahead of the trip to their promotion rivals.
The duo have been sidelined since early in the season but made their comebacks for the reserves this week.
Club captain and long-serving midfielder O'Connor suffered an ankle injury in November and striker El Alagui has been out with a knee injury since October.
But both came through an hour of action on Monday afternoon, so boss Uwe Rosler must decide whether to take them to Bramall Lane or give them another reserve run-out first.
Defender Scott Barron (hip) and back-up goalkeeper Richard Lee (shoulder) have undergone operations and will be out for the rest of the season.