The Blues were out of action on Boxing Day after postponing their game with Swindon at Fratton Park.
Jack Whatmough and four other players tested positive for coronavirus.
And the Imps took full advantage to move back to the summit of the table as they eased past the struggling Brewers 5-1 at Sincil Bank.
Michael Appleton’s men took the lead after just four minutes when Remy Howarth slotted home.
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Lincoln doubled their advantage only three minutes later through Brennan Johnson’s close-range effort.
The home side stepped their foot on the gas in the second period, with Anthony Scully increasing the lead before Johnson bagging his second.
Kane Hemmings notched a consolation for Burton before Harry Anderson restored the four-goal advantage.
The Imps are now three points clear of second-placed Pompey having both played 19 matches.
Meanwhile, Charlton moved into the play-off places after coming from behind twice to draw with Plymouth 2-2 at the Valley.
Luke Jephcott fired a double for the Pilgrims while Chris Gunter and Marcus Maddison were on target for the Addicks.
Last season’s beaten play-off finalist Oxford delivered a much-needed win over AFC Wimbledon.
First-half goals from Jordan Obita and Matty Taylor inspired the 2-0 success at the Kassam Stadium.
Following a stuttering start, MK Dons are steering clear of the drop zone after defeating Bristol Rovers 2-0.
Ben Gladwin got the breakthrough in first-half stoppage-time before talisman Scott Fraser wrapped up the three points for Russell Martin’s men following the interval.
Former Pompey boss Steve Cotterill is still unbeaten in the league since taking charge at Shrewsbury.
But they were forced to battle back against crisis-club Wigan to earn a 1-1 draw at the DW Stadium.
Will Keane opened the scoring for the Latics but that was cancelled out by Shaun Whalley’s effort.
Fleetwood were held to a 1-1 stalemate at Crewe Alexandra.
Meanwhile, Blackpool v Rochdale, Doncaster v Accrington, Gillingham v Peterborough, Ipswich v Northampton and Sunderland v Hull were all postponed because of positive coronavirus cases.