Lions' and Boro's Championship challenge
Like Millwall, Middlesbrough's impressive run in the FA Cup has coincided with a dip in League form which has seen Tony Mowbray's men pick up four points from their last eight games.
However, Boro are still in sixth spot, with the second best home record in the Championship and will be formidable opponents ahead of next week's Fifth Round Cup-tie against Chelsea.
Mowbray will again be without key players; Stuart Parnaby (hamstring), Lukas Jutkiewicz (ankle), Jonathan Woodgate (calf) and Seb Hines (knee), whilst Scott McDonald has only just returned to training.
Undoubtedly the injury crisis at the Riverside has contributed to Boro's recent inconsistent form and Millwall will be looking to restore some confidence of their own by arresting the recent five game losing streak in the North-East.
Chris Taylor is not ready for first team duty yet, Jack Smith and Paul Robinson are still rehabilitating and Shane Lowry serves a one match suspension. Nathan Tyson returns to the squad as do Danny Shittu and Liam Feeney.
Kenny Jackett is under no illusions about the seriousness of his team's current League form, saying: "While I thought there were positives in our performances against Hull City and Blackpool recently, on Tuesday night we were poor all round. We have to get that out of our system quickly, individual players have to rediscover their form and we have to show some character in a very difficult game to turn things around."
Millwall can take encouragement from their last two visits to the Riverside, where they picked up a draw in 2011/12 and a win the previous season, on both occasions arresting a run of poor form.
A brace from Andy Keogh added to a Liam Trotter strike earned The Lions all three points (3-1) when the teams last met at The Den back in September.