Holloway has won just two of his 13 league games in charge at the New Den since replacing Steve Lomas in January, and saw his side beaten 2-1 at Leeds United on Saturday.
Third-bottom Millwall now face a home match against Birmingham in midweek, with the Midlanders sitting five points and two places above them in the Championship.
The other sides involved in the relegation scrap all face daunting matches against teams in the top seven on Tuesday, with Yeovil Town visiting leaders Leicester City, Barnsley travelling to Reading and Charlton Athletic playing out-of-form Nottingham Forest.
"The Birmingham game is a massive one for us now. We have to try and drag them into it," the former Crystal Palace manager said.
"It's a must win. I've never had a more important game in my life."
Sean Dyche's men remain 10 points clear of third-placed Derby County with nine games to go, and will look to extend their unbeaten run to 15 league games.
Doncaster's win over Wednesday saw them climb above Birmingham and put eight points between themselves and the bottom three, but with a tough run-in including matches against Leicester, Derby and Reading after their trip to Burnley, Paul Dickov's side are not yet certain to survive.
Derby boss Steve McClaren, meanwhile, will hope Saturday's 5-0 thumping of local rivals Forest - his side's first win in five outings - will act as a catalyst for a late-season push to catch Burnley, beginning at ninth-placed Ipswich Town.
Play-off rivals QPR and Wigan Athletic will go head-to-head at Loftus Road, and the visitors know victory over Harry Redknapp's men will move them just a point behind their opponents.
Elsewhere, Bolton Wanderers and Blackpool meet at the Reebok Stadium, while Huddersfield Town entertain Middlesbrough, Blackburn Rovers travel to Watford and Leeds are Bournemouth's visitors at Dean Court.
