Five-goal Haaland fires Man City into last eight
The Norway international scored twice in the space of two minutes at the Etihad Stadium on Wednesday (AEDT) to reach 30 in the competition, before adding a third on the stroke of half-time.
At just 22 years and 236 days old, Haaland was the youngest man to that mark – 116 days younger than previous record holder Kylian Mbappe.
Other players he trumped included Lionel Messi (23 years and 131 days) and Raul (24 years and 91 days).
It was not the only record Haaland shattered either, with the forward's 30th Champions League goal coming in just his 25th game, setting a new benchmark for the fewest matches required to reach that milestone.
He blew away the previous record of 34 matches, held by Ruud van Nistelrooy, while also bettering the 46 games it took Robert Lewandowski to achieve the feat.
Haaland had not scored in the first leg against Leipzig in Germany, heading into Tuesday's match with 28 goals in Europe's top competition.
A harsh penalty awarded against Benjamin Henrichs allowed him to move one closer to the milestone in the 22nd minute, before he nodded home a rebound when Kevin De Bruyne hit the crossbar moments later.
Haaland then added a third – his 31st in the Champions League – when he poked in after a Ruben Dias header was stopped just shy of the goal line following a corner in first-half stoppage time.