Two of the sides above them extended their advantage with wins, but none of those immediately below them were able to take advantage of the Blues’ inactivity.
Hull are back on top – albeit only on goal difference – thanks to a fifth-minute Greg Docherty goal that earned them a 1-0 home win over Swindon.
Knocked off their perch were Lincoln City, who had two penalties saved in a 1-0 home loss to Doncaster, who move third courtesy of Taylor Richards’ first-half winner.
Peterborough remain only two points in front of Kenny Jackett’s men after a surprise 2-0 defeat at Shrewsbury, who won thanks to Harrison Chapman’s second-half goals.
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Sunderland blew a chance to leapfrog Pompey when they conceded a late equaliser at home to Gillingham.
Aiden McGeady twice put the Black Cats ahead but Alex MacDonald and Jordan Graham struck to claim a point for the Gills, with Graham’s goal in injury time.
It was Sunderland’s 10th draw in their 24 games.
Oxford United are climbing the table in menacing fashion.
Their 1-0 home victory over Fleetwood through Josh Ruffels' goal just before the half-hour leaves them eighth – and having now won seven in a row.
Accrington led twice at Home Park through goals from Joe Pritchard and Dion Charles but Plymouth forced a 2-2 draw after Luke Jephcott and Niall Ennis were on target.
Also sharing League One spoils were mid-table duo Crewe and Ipswich. Alexandra went ahead through Charlie Kirk on 59 minutes but Andre Dozzell levelled 14 minutes from time.
MK Dons won 2-0 on their visit to bitter rivals AFC Wimbledon with strikes from Matt O’Riley and Matthew Sorinola.
Rochdale won 2-1 at Bristol Rovers.
The Northampton-Wigan and Blackpool-Burton games were called off.