The hosts were searching for a seventh successive win, something they last achieved in 1964, but found themselves 1-0 down on 18 minutes when Anguissa ran onto a long ball on halfway, and used all of his strength and skill to get the better of Sam Beukema before calmly rounding Łukasz Skorupski to tuck home a lovely individual effort.
That was the first real chance of the night, and it also proved to be the Bologna goalkeeper’s last involvement, as he limped off injured just moments later.
His replacement, Federico Ravaglia, was soon on hand to push a Scott McTominay shot around the post, before dashing off his line to make a splendid stop at the feet of Matteo Politano.
Vincenzo Italiano’s side on the other hand were struggling to show the same attacking prowess that had seen them put Lazio to the sword in a 5-0 victory in their previous home game.
Their sole effort on target in the first half was a tame Jens Odgaard header that Simone Scuffet was comfortably equal to, while Michel Aebischer whipped just off target in injury time.
They were more lively after the break though, as Thijs Dallinga called the goalkeeper into action for a second time, while Riccardo Orsolini lifted a fizzing, angled left-footed effort over the far corner.
I Rossoblù duly got the equaliser they deserved in sensational fashion, as Jens Odgaard cut back a cross to the lively Ndoye at the near post, and he somehow, with back to goal, flicked home a remarkable effort that bounced in off the crossbar.
Given no team has rescued more points from losing positions in Serie A this season than Bologna, it was hardly a surprise that they responded. What was a shock was how ineffective Napoli proved to be, as they struggled to even get out of their own half of the field.
They were hanging on as Scuffet pushed Juan Miranda’s swinging free-kick over the bar, while substitute Santiago Castro missed a sitter in the 90th minute, unbelievably skewing a rebound wide from inches out after Emil Holm’s initial header had been superbly saved.
The result means Bologna, who have now won just three of the last 19 H2Hs, are on course to make it back-to-back UCL qualifications for the first time in their history, while Napoli, who had a last-gasp Giacomo Raspadori strike superbly saved after it deflected off Mathías Olivera’s back, are winless in five away matches.