In his pre-match press conference, manager Graham Alexander confirmed that central defender Charlie Goode will be missing for the rest of the season.
The 21-year-old landed both awkwardly and heavily on his ankle following an aerial challenge and suffered ligament damage as a result.
Speaking about the injury, Alexander said: "Charlie unfortunately is going to miss the rest of the season as he's damaged he's damaged his ankle ligaments so we won't see him back fit with us until pre-season.
"It's a real difficult one for us and it was a freak injury really. He's gone up for a header, landed awkwardly and he's a big lad so there's a lot of force going through that ankle when he landed wrongly. It's bad news for Charlie and for us.
"He's going to be doing a lot of work over the summer and pre-season is so vital for players, so we want him to be back for that. He's a dedicated lad so he will work really hard."
"He trains magnificently and he's always ready to play. We've missed a number of big players this season and still managed to pick up results, so we're going to have to do the same without him."
Missing from the game against Bradford City and expected to sit out again is midfielder Sam Mantom and striker Kevin van Veen. The United boss stated both have gone for follow-up scans to look at the extent of their injuries.
"Sam and Kev won't be available for the weekend either," Alexander continued.
"They've both gone for scans today (Wednesday) - further scans - to see how they are and to see how we treat their injuries from now. We will find out later on today how they are, but they'll definitely not be involved at the weekend.
"We're not surprised with Sam, but we felt Kev had an outside chance of being able to train this week, but he's not trained up until this point.
"Their progression has plateaued out a little bit, which is why we've taken them for further diagnosis."
See much more from Graham Alexander and Matt Crooks previewing the Millwall encounter on The Iron PlayerHD.