Reading midfielder Mikele Leigertwood and striker Simon Church are hoping to prove their fitness.
Leigertwood, whose loan spell from QPR was made permanent in May when he signed a three-year deal, has been struggling with a knee injury while Church is also doubtful for the season's opening game due to a thigh strain.
Should Leigertwood fail to make it, manager Brian McDermott will turn to Brian Howard or Brynjar Gunnarsson.
Forward Noel Hunt has proved his fitness in the last two warm-up matches and is in contention to start but McDermott will be without suspended midfielder Jay Tabb.
Tabb, a substitute in Reading's play-off final defeat to Swansea in May, was sent off at half-time for comments made to match officials and will subsequently miss the first two games of the season.
Millwall will check on Paul Robinson and Liam Trotter ahead of Saturday's game.
Lions skipper Robinson made his return from a summer knee operation in the 4-3 friendly win over Charlton last weekend and will start at centre-half if boss Kenny Jackett feels he is fit enough.
Midfielder Trotter has been suffering with a thigh strain but is also expected to be okay to travel.
Goalkeeper David Forde missed a chunk of pre-season with an ankle injury but he is now fit.
Striker Shaun Batt is the only long-term absentee and he is back in training after a cruciate injury.
Summer signings Therry Racon, Darius Henderson and Jordan Stewart are all expected to make their debuts.