Peterborough United chairman Darragh MacAnthony said that he was disappointed by the attendance at London Road for Wednesday's win over Colchester United.
The Irishman took to Twitter to express his regret at the low turnout.
Close to 20,000 Posh fans roared Posh to victory in the Johnstone's Paint Trophy final at Wembley last weekend, but only 4,434 turned up for the 2-0 win over the U's in midweek.
With Posh hoping to push for a return to Wembley later in the season for the League One play-off final in May, MacAnthony says that his team need the fans to back them.
On the pitch, Posh were always in control against a poor Colchester United side that offered little attacking threat.
Joe Dunne's outfit didn't muster a single shot on target and are still in trouble at the wrong end of the division.
Peterborough captain Tommy Rowe opened the scoring midway through the first half as he headed in Grant McCann's corner.
Top scorer Britt Assombalonga then put the game beyond any doubt in the second half as he cooly slotted past Sam Walker in the Colchester goal.
The win means that Peterborough now have a four point gap to the nearest play-off challenger, with games running out for the chasing pack to overtake them.