Pompey players Christian Burgess and Stuart O'Keefe were part of the massive away support who witnessed a dramatic Blues win at MK Dons today.
Kenny Jackett's side snatched a memorable late victory at Stadium MK thanks to goals from Matt Clarke (84 minutes) and Conor Chaplin (94), following Ike Ugbo's first-half opener for the hosts.
And there to help them over the line were 6,257 away supporters, including Burgess (suspended) and O'Keefe (injured), who left happy after their side's come-from-behind win.
Today's official away attendance is Pompey's biggest of the season.
That record was originally set in December, when 3,870 of the Fratton faithful witnessed the Blues' 1-0 victory Charlton at The Valley.
Last season’s League Two promotion-winning game at Notts County has also been surpassed.
For that memorable 3-1 victory, 4,366 Pompey supporters descended on Meadow Lane – with the majority invading the pitch after full-time in celebration.