Meet Millwall's League One opponents
Stadium: Abax Stadium
Nickname: The Posh
Position: Ninth in League One
Manager: Dave Robertson was appointed as Peterborough United manager on a three-year contract in May this year.
The 41-year-old had been in charge as caretaker boss since Darren Ferguson left the Abax Stadium in February 2015.
Under Robertson, Posh won six of their 15 games, drawing four and losing five as they finished ninth in League One.
He will be assisted by Grant McCann, 35, who spent five years as a player with Peterborough and had a further spell with Irish club Linfield.
Robertson's path into management is an interesting one, and certainly different. A Royal Marine at 17 and awarded the coverted green beret, his first tour of duty was to Kuwait at the end of the Gulf War.
He left the Marines in 1998, but during his time with them had undertaken a week's coaching course in Portsmouth and it was that career path he then followed. Robertson spent two years at Posh, arriving back at London Road to work with the youth set-up in 2003 via a two-year spell in America and then Crystal Palace.
Having overseen the development of many young players in his role as Academy Manager, Robertson stepped up to take temporary charge of the first team when Ferguson was sacked on 21st February 2015 and will be looking to his new challenge with a fair amount of optimism following his successful time as interim boss.
Key Player: Joe Newell may have picked up two Player of the Year awards and Conor Washington topped the scoring charts, but the versatility and consistency of Michael Bostwick since joining Posh in July 2012 has been crucial.
Originally signed as a combative midfielder, Bostwick has played a significant number of his games for Posh in the back four, both at centre-half and right-back.
Bostwick started out on the books right here at The Den as a youngster and was a regular for both the U18s and then moved up to play for the reserves.
He was twice sent on loan to Crawley Town, making 32 appearances and scoring five goals before joining Rushden & Diamonds on a permanent 18-month contract in January 2007.
The Eltham-born 27-year-old's time at Rushden came to an abrupt halt when he fell out of favour at Nene Park and he was on the move again. A season at Ebbsfleet followed before he switched to Stevenage in 2008, spending four successful years there during which the club recorded back-to-back promotions.
The former Lion has been at Posh for nearly three years and has been a key member of their squad ever since.
Top scorer: Conor Washington (13 goals)
Head-to-head: There have been just 28 previous encounters between Posh and The Lions - and Millwall edge the stats with 13 victories to Peterborough's nine in the League and League Cup. The teams have yet to be drawn against each other in the FA Cup competition but have lined up in four League Cup ties, winning two apiece.
Recent history favours Millwall, who have been on the losing end just twice in the past eight matches of which they have won four and drawn the other two.
Last time we met: 'Ouch' is probably the best word to describe Millwall's last game against Peterborough at The Den in February 2013.
Posh started on the front foot and Lee Tomlin fired the first of his two goals after seven minutes with Millwall levelling through James Henry's chip six minutes later.
However Posh, who had started the game at the foot of the Championship table, were in rampant mood and rattled in a further four goals. Skipper Tommy Rowe fired the visitors ahead and after the break George Boyd supplied Tomlin for his second.
Nathaniel Mendez-Laing scored before Shane Lowry was sent off for a foul on Dwight Gayle. Boyd rubbed salt into the wounds with a stunning solo effort to complete the rout with three minutes remaining.
Millwall: Forde, Lowry (s/o 67mins), Smith (Dunne, 46mins), Beevers, Osborne, Trotter, Henry, Abdou, Hulse (Marquis, 84mins), Afobe (Woolford, 46mins), Keogh. Subs not used: M.Taylor, Malone, Wright, N'Guessan.
Scorer: Henry (12mins)
Peterborough Utd: Olejnik, Zakuani, Little, Bostwick, McCann, Rowe, Ferdinand (Payne, 86mins), Mendez-Laing (Swanson, 77mins), Tomlin (Newell, 90mins), Boyd, Gayle. Subs not used: Day, Alcock, Brisley, Knight-Percival.
Scorers: Tomlin (7, 54mins), Rowe (31mins), Mendez-Laing (58mins), Boyd (87mins)
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