The Kent side would have moved above Port Vale into pole position with victory over York - but they had to settle for a 1-1 draw with the mid-table visitors.
It would have been worse for Martin Allen's men had Cody McDonald not netted in the 85th minute, cancelling out Charlie Lee's 17th-minute own goal.
Rotherham were another side to disappoint at home, slipping out of the play-off positions with a 3-1 defeat against Bristol Rovers.
Rovers led two minutes before half-time through Lee Brown's penalty, before Claude Davis - who gave the spot-kick away - picked up a second yellow card.
Ellis Harrison (52) and Joe Anyinsah (61) made the man advantage count as Rovers moved off the bottom of the table at AFC Wimbledon's expense. David Noble pulled a goal back for the visitors 17 minutes from time.
Jacques Maghoma's fourth-minute penalty proved enough for Burton to see off Barnet and maintain their play-off push, while Southend won by the same margin at Chesterfield, with Gavin Tomlin's 83rd minute goal proving decisive.
Fleetwood returned to winning ways with a 3-0 win over Oxford. Jamille Matt set the ball rolling in the eighth minute, before Ryan Crowther (58) and Jon Parkin (86) wrapped up a win which moves the hosts to within goal difference of the play-offs.
Goals inside the last nine minutes from Stewart Drummond and Ryan Williams gave Morecambe a 2-1 win at Dagenham & Redbridge which moves them further clear of the relegation zone. Luke Wilkinson had given the hosts a 61st-minute lead.
Plymouth and fellow strugglers Accrington could not produce a goal in their Devon clash, a result which does neither side any favours in their quest to stay in the Football League.
