Derby boss Gary Rowett could make a number of changes to his side ahead of the busy Christmas period with four matches in eight days.
Tom Lawrence (ankle), who missed last weekend's victory over Aston Villa, was due to train on Thursday, while Andreas Weimann (knock) - on target in each of the last two games before going off injured against Villa - was on the training pitch on Tuesday and both players will be assessed ahead of the visit of Millwall.
Striker Johnny Russell is pushing for a start in Rowett's starting line-up after impressing off the bench in recent weeks - including scoring the winner in a 1-0 victory against Burton at the start of the month and he was also on target last time out.
Fourth-placed Derby host the match on the back of three league wins without conceding a goal and they count just two goals against from their previous seven fixtures.
Millwall manager Neil Harris could name an unchanged side at Derby following their 2-1 win over Middlesbrough last weekend.
Midfielder Shaun Williams will be pushing for his first start since September after coming on as a substitute in Millwall's last two matches.
Fred Onyedinma and Shane Ferguson (both knocks) remain sidelined.
Byron Webster is also unavailable, but is back in the gym as he continues his rehabilitation from a serious knee injury.