All you need to know ahead of Saturday's crucial gameMillwall head to the Riverside Stadium on Saturday (3pm) looking to build on a four-game unbeaten run which has seen The Lions rise to within one point of the safety zone.
Boss Ian Holloway says his side can't afford to let results elsewhere act as a distraction ahead of kick-off. Relegation rivals Charlton, Doncaster, Yeovil and Blackpool all play on Friday, but Ollie has told Lions Player that his men must focus only on their own jobs at the Riverside Stadium. See his pre-match interview in full here.
The Lions will be without midfielder Ed Upson, who looks set to sit out the remainder of the campaign with an ankle injury. Upson would have missed Saturday's game through suspension anyway, but sustained an injury in training this week which will keep him out of his side's vital Championship run-in.
Richard Chaplow returned to training this week after a long-term achilles problem but Danny Shittu remains sidelined with a similar injury that will keep him out for the rest of the season.
Middlesbrough boss Aitor Karanka will be without Daniel Ayala and Ben Gibson, who are both suspended. Kei Kamara, Mustapha Carayol, Seb Hines and Rhys Williams remain sidelined, but former Lions loanee George Friend is expected to return from a slight muscle strain.
Last Saturday's 2-2 draw with Watford extended Millwall's unbeaten streak to four games, a run which has seen The Lions climb to within touching distance of their relegation rivals placed just above them in the table.
Ollie's men have won their last two away games - at Nottingham Forest and Wigan - and know a third straight victory on the road could see them rise out of the drop zone.
Middlesbrough are in even better form and go into Saturday's encounter with four straight wins under their belts. Those victories came against Brighton, Derby, Birmingham and, most recently, promotion hopefuls Burnley.
Karanka's men are 12th - six points outside the Play-Off places - and have lost just three home games all season, the fewest of any club outside the top six.
Millwall's record at Middlesbrough doesn't make for great reading with The Lions recording just three wins in their previous 22 visits. Two of those victories, however, have come in the last three seasons.
This weekend marks the 49th match between the two clubs. The Lions have won 17 of the previous 48 encounters to Middlesbrough's 20. Eleven matches have ended all-square.
In the reverse fixture earlier this season, Boro came away from The Den with a 2-0 victory thanks to goals from Emmanuel Ledesma and Albert Adomah.
Full match commentary will be available on Lions Player from around 2.50pm.
You can also keep up-to-date with the action as it happens on The Wall and on the club's official Twitter account @MillwallFC. Join in the conversation using this week's matchday hashtag, #MFCvMFC.
For a comprehensive list of odds on the game, visit Sky Bet