JOE Martin is serving a one-game suspension after picking up his fifth yellow card of the season against Southend last Saturday.
Shane Ferguson is the obvious option to replace Martin with Lee Gregory coming back into the starting XI for the first time in seven games and Aiden O'Brien dropping to the left of midfield.
Alternatively, Harris could decide to hand starts to either Sid Nelson or Noah Chesmain, who were both part of a Millwall U23 side that kept a clean sheet against Nottingham Forest on Monday.
Millwall haven't kept a clean sheet in the league since the opening day, and defenders Shaun Cummings and Shaun Hutchinson are still out.
Rochdale are in 23rd place in the League One table, but defeated Fleetwood 2-1 last weekend, their first league win since the last day of last season.
Reuben Noble-Lazarus and Ollie Rathbone are back in training but won't be considered this weekend.
Millwall are looking for their first league win in four games on Saturday. A year ago, goals from Jimmy Abdou, Shaun Williams and Steve Morison gave Millwall a 3-1 win over Keith Hill's side, their first victory at home in the league in 2015-16 after four straight defeats at The Den.
Millwall record against Rochdale:
Won 6 Drawn 2 Lost 2
Probable Millwall team:
Millwall: 4-4-2: Archer; Romeo, Nelson, Webster, Craig; Worrall, Thompson, Williams, Ferguson; Gregory, Morison.
Millwall 5/6 Draw 13/5 Rochdale 16/5
Image source: ©Millwall FC