Swindon will be boosted by the return of midfield duo Simon Ferry and Alan Navarro.
Ferry has been missing since the 4-1 win over Crewe on April 16 with a hamstring injury while former Brighton man Navarro has been sidelined with a similar problem since the previous week.
But both players are back in training and in contention to feature at the County Ground.
Young striker Miles Storey has also rejoined the squad in full training after his hamstring tear but is unlikely to feature.
Tommy Miller made his comeback from a calf injury against Scunthorpe last weekend and looks likely to be on the bench as the Robins look to move closer to recording back-to-back promotions.
Brentford have added Paul Hayes to their squad ahead of Saturday's tie.
Striker Hayes is back with the Bees after a loan spell with Crawley and manager Uwe Rosler admitted he could be involved over the two legs, which begin at Swindon's County Ground on Saturday.
Rosler has no new injury concerns following last weekend's dramatic 1-0 defeat by Doncaster, which denied the Bees automatic promotion.
Defender Tony Craig is still suspended, but he will be available for the second leg at Griffin Park on Monday.
Captain Kevin O'Connor will deputise at centre-half again in Craig's absence and is likely to take the penalties should Brentford be awarded any after Marcello Trotta's now infamous miss against Rovers on Saturday.