The 2011-12 season will forever go down as one of the most memorable in the history of the English game.
Manchester rivals United and City battled it out for the main prize, with the race going right down to stoppage time in the final encounter of the campaign.
Rooney found the net on 27 occasions, while Argentine Aguero, in what was his debut campaign in England, fired in 23 goals for City. Only Arsenal frontman Robin van Persie (30) scored more.
The duo's respective totals were partly reached thanks to hat-tricks that they both scored in fixtures that took place three years ago today.
Rooney's trio of goals came at the Reebok Stadium, where United ran out 5-0 winners against Bolton Wanderers. His first came from a Phil Jones cross, and the United defender played a big role in Rooney's second when his shot rebounded to the centre-forward off goalkeeper Jussi Jaaskelainen.
He saved his best until last, though, as he completed his hat-trick - his second in successive encounters - when he swept in Nani's pass from the edge of the penalty area, with Javier Hernandez adding United's other two goals.
Meanwhile, at the Etihad Stadium, Aguero was putting Wigan Athletic to the sword by scoring all three of his side's goals. The summer signing from Atletico Madrid took just 13 minutes to break the deadlock when he turned in a cutback from David Silva.
His second and third goals came in the second half and after Carlos Tevez had missed from the penalty spot. On both occasions Aguero was released by a teammate, before going on to get the better of visiting goalkeeper Ali Al-Habsi.
Despite the fact that Rooney would go on to score four more goals overall, it would be Aguero and City that were be celebrating come May 2012.