City opened the scoring in the fourth minute when Kevin de Bruyne, who assisted the first four goals, was allowed time and space to cut the ball back for Haaland to convert.

The pair combined again 15 minutes later, with Haaland running on to a through ball before powering it past Luton goalkeeper Tim Krul and it was a similar move that brought the third, only this time with a delicate dink to finish.

Jordan Clark pulled one back for Luton with a stunning strike, curled beautifully into the top corner from 25 yards on the stroke of half-time and gave Rob Edwards’ side hope of a memorable comeback with a thumping finish seven minutes into the second half.

However, Pep Guardiola’s team soon dashed those hopes when De Bruyne squared for Haaland to tap into an empty net after a superb pass from Kyle Walker had sent the Belgium midfielder clear.

Haaland got his fifth – matching his effort against RB Leipzig in last season’s Champions League last 16 – when his low shot went straight through Krul, who then saw a long-range strike from Mateo Kovacic flash past him for the visitors’ sixth.