Riyad Mahrez put in a transfer request to try to force through a transfer to the Etihad Stadium but after City refused to meet Leicester's valuation, the Algerian worldwide spent a week away from the training ground.
But it didn't take long for the home side to show the abundance of talent they have going forward despite missing out on Mahrez and coping with a series of injuries to the likes of Leroy Sane and Gabriel Jesus.
One man who was more responsible than others for the defeat was Foxes goalkeeper Kasper Schmeichel.
The Denmark global should have done much better with Aguero's strike for the third City goal, and then the Leicester stopper presented the ball straight to the Argentine forward for the fourth to round off a thoroughly rotten day for the 31-year-old. "We have had three massive games against (Manchester) United, Liverpool and Arsenal and seven points is good". The great players buy themselves time, the game looks like it stands still when they've got the ball and De Bruyne has that capacity.
Claude Puel believes that it is time to stop talking about Riyad Mahrez after giving the winger a 30-minute runout from the bench against Manchester City. He could feature as a second-half substitute, while he should regain his spot in the starting XI Feb. 24 against Stoke City. While Sterling, Aguero and Bernardo Silva all made darting runs between the defenders, the attacking impetus of Guardiola's side had certainly decreased, but Leicester's was nearly non-existent.
Manchester City lead the EPL table with 69 points, 13 ahead of second-placed Manchester United.
Aguero got his second goal in just five minutes in the 53rd minute. It was a brilliant way to grab his third goal, and finished off Leicester completely in emphatic style.
MANCHESTER, ENGLAND - NOVEMBER 05: Kevin De Bruyne of Manchester City controls the ball while under pressure from Alexis Sanchez of Arsenal during the Premier League match between Manchester City and Arsenal at Etihad Stadium on November 5, 2017 in Manchester, England. For Leicester, Jamie Vardy's presence made all the difference in the first half.