The champions claimed all three points despite seeing France international Eliaquim Mangala dismissed with 15 minutes remaining at St Mary’s after the centre-back picked up a second yellow card.
However, second-half goals by Yaya Toure, substitute Frank Lampard and left-back Gael Clichy allowed the north-west outfit to cut the gap on Chelsea at the top of the table to just six points after the Blues were held at Sunderland on Saturday.
Clichy added the third after 88 minutes when Aguero again unselfishly picked out his unmarked team-mate at the back post, with the Frenchman scoring his first-ever goal for the club with a simple finish.