Find out the head-to-head record and more
Posh side slipped to their first defeat of the campaign at the weekend when Bradford City edged a tight match 1-0 at the AMAX Stadium and The Lions, who themselves let a 2-0 lead slip in a 2-2 draw at MK Dons, will want to continue their unbeaten start to the season.
The third - and most recent - meeting came on 20th February when a brace from Steve Morison either side of a Lee Gregory header moved Millwall up to fifth in the League One table.
That defeat for Posh came during a poor sequence of results that saw the men from London Road lose six in seven games, a run that was to ultimately kill off any aspirations they had of challenging for a Play-Off spot.
Tuesday night's game at the AMAX Stadium could see former Lion Michael Bostwick come up against the club where he started his career, having played in Millwall's youth team alongside the likes of Curtis Weston, Preston Edwards and Ross Gaynor.
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