The Imps looked on course to put Wednesday’s 6-0 home thrashing against West Ham behind them in style when goals from Andrei Coubis and Rob Street put them in a strong position after 33 minutes at The Den.

But the Lions were able to prevent back-to-back home defeats with a much-improved second-half performance, with the visitors hanging on for a share of the spoils after having Deji Elerewe sent off soon after Cooper’s leveller.

Lincoln had the perfect pick-me-up after their midweek hiding as they scored after just 25 seconds when the ball was cleared as far as Coubis and the Romanian defender fizzed a low strike from outside the box that went in off the far post.

Stunned by the early opener in what was the first meeting between the two clubs since 1999, Millwall pressed for a quick response as Kyrell Lisbie slashed a shot wide from Lyndon Dykes’ long throw.

The Imps then doubled their lead in the 33rd minute when Street’s shot went through the legs of Millwall goalkeeper Filip Marschall.

There was some controversy around the goal, though, as what looked a clear handball by Reeco Hackett in the build-up was missed by the assistant stood close by.

Somehow, Lincoln failed to add to their tally five minutes into the second half when Freddie Draper’s header from Adam Reach’s cross hit the post before Dom Jefferies struck the same upright with his follow-up.

Millwall finally began to rally after the hour mark, with Dykes nodding Zak Sturge’s ball into the box across for Luke Cundle whose header was clawed away by George Wickens.

And they were back in the game after 63 minutes when Camiel Neghli’s low cross found its way to Lisbie who saw his initial effort blocked before he quickly sorted out his feet to slide in his first goal for the Lions.

The Imps almost restored their two-goal cushion within a minute, however, when Draper’s shot across goal was pushed out by Millwall’s substitute goalkeeper Max Crocombe, with the rebound just evading Hackett.

Lisbie then looked certain to equalise for the hosts when Romain Esse’s ball into the box was deflected into his path, but Wickens stood strong in making a big save.

But Millwall were level in the 82nd minute when Cooper managed to force the ball in from close range after Lincoln were unable to clear Ryan Leonard’s corner.

The visitors then had to survive the final six minutes, plus stoppage time, with 10 men after Elerewe was sent off for fouling Zak Lovelace when the last man.