As many as eight points separate the sides on the table but neither has much to fight for, with safety already assured.
The Lions even had the chance to qualify for the play-offs until four weeks ago, when a series of wins put them in with a shout. However, a drop-off in form that yielded just one point from the 12 available in the next four games has put paid to those hopes.
Gary Rowett's side now languish 12th in the standings, but have a chance to finish inside the top-10, which could be a consolation prize.
Bristol City are six places adrift of them, having continued their poor form under Nigel Pearson, who's been unable to turn the fortunes of the side since taking over in February.
Yet the former Leicester City boss recently signed a new three-year deal with the Robins, tying himself to the club for a few more years.
Millwall vs Bristol City Head-To-Head
There have been exactly 100 games between the sides before, with Bristol winning 36 times over Millwall, who've beaten them on 32 occasions.
They've already met twice this season, including once in the FA Cup, which went Bristol's way, but their league meeting ended in a 2-0 victory for Millwall.
Millwall Form Guide (all competitions): W-L-D-L-L
Bristol City Form Guide (all competitions): L-D-D-L-L
Millwall vs Bristol City Team News
Shaun Hutchinson, Ryan Leonard and Murray Wallace are all out for Millwall, but Alex Pearce is available again after missing out on the Watford defeat last time.
Another change could be Kenneth Zohore coming into the side in place of the out-of-form Tom Bradshaw, who hasn't scored in 17 games!
Injured: Shaun Hutchinson, Ryan Leonard and Murray Wallace
The Robins are without the injured triumvirate of Andreas Weimann, Chris Martin and Jay Dasilva, but there are no fresh injury concerns.
Kasey Palmer and Antoine Semenyo are pushing for a start after coming off the bench last time, while Nahki Wells could get the nod again considering his good record against Milwall.
Injured: Andreas Weimann, Chris Martin and Jay Dasilva
Millwall vs Bristol City Predicted XI
Millwall (3-5-2): Bartosz Bialkowski; George Evans, Alex Pearce, Jake Cooper; Mahlon Romeo, Jed Wallace, Maikel Kieftenbeld, Billy Mitchell, Scott Malone; Kenneth Zohore, Mason Bennett.
Bristol City (4-3-3): Daniel Bentley; Jack Hunt, Zak Vyner, Tomas Kalas, Tommy Rowe; Henri Lansbury, Adam Nagy, Tyreeq Bakinson; Antoine Semenyo, Nahki Wells, Kasey Palmer.
Millwall vs Bristol City Prediction
Millwall are looking to make their first league double over the Robins since the 1992/93 season, but that's unlikely to happen.
Both sides have been in poor form lately and we're expecting a low-scoring draw here.
Prediction: Millwall 1-1 Bristol City