Sergio Aguero scored a goal in his comeback as Manchester City swept past second-tier Blackburn Rovers with an emphatic 5-0 victory on Wednesday in their FA Cup third-round replay.

Held 1-1 at Ewood Park in the initial tie, City took control of the replay at a rain-soaked Etihad Stadium via a brace of goals either side of halftime from Alvaro Negredo.

Edin Dzeko added a third before Aguero scored only 50 seconds after his introduction as a 72nd-minute substitute, following a month on the sidelines with a calf injury.

Dzeko brought up City’s 99th goal in all competitions this season to make it 5-0, leaving Blackburn’s Championship counterparts Watford with plenty of food for thought ahead of their trip to the Etihad in the fourth round.

City manager Manuel Pellegrini made eight changes to the team that won 2-0 at Newcastle United on Sunday and his new-look side initially struggled to make inroads.

Dzeko snatched at a handful of early chances and a free-kick within shooting distance offered Blackburn an opportunity to strike at the other end, only for Ben Marshall to curl his shot straight at Costel Pantilimon.

City began to muster more of a threat, with Javi Garcia forcing Blackburn goalkeeper Paul Robinson into a sprawling save from long range and Jesus Navas bending an inviting cross across goal.

Blackburn had largely succeeded in keeping their opponents at arm’s length but, with halftime approaching, City struck.

Navas’s pass found the overlapping Fernandinho and the Brazilian’s whipped cross enabled Negredo to claim his 20th goal of the season with a firm header.

Pellegrini introduced Aleksandar Kolarov for Fernandinho at halftime and the Serbian created City’s second goal with a superb pass from halfway that Negredo lifted past Robinson.

Dzeko made the game safe in the 67th minute when he swept in a shot high into the net from Navas’s low cross.

Aguero came on for Negredo and needed only two touches to make his mark, trapping a lay-off from Dzeko and swivelling before planting a low shot in the bottom-right corner with his left foot.

Dzeko added a fifth with 11 minutes remaining, finishing at the near post after the irrepressible Navas drove in another excellent cross.