City took the lead after only 65 seconds at Etihad Stadium, when Erling Haaland's errant shot struck Luton's Daiki Hashioka before falling into the goal. It took City more than an hour to extend their lead, thanks to Mateo Kovacic's wonderful, rising shot from near the edge of the area.
After Fred Onyedinma fouled Jeremy Doku, Haaland converted a penalty to seal the victory. Just after City made a double substitution, Ross Barkley capitalized on Matheus Nunes' error to score one for the Hatters. But Doku cut in from the left and scored a fantastic solo goal into the bottom corner. Josko Gvardiol finished the 5-1 rout seconds before the final whistle. City controlled the encounter, with 73.7% possession and 37 shots to the visitors' four. City now cannot afford to rest on their laurels as they take on Real Madrid in the second leg of their Champions League quarterfinal on Wednesday.