The City boss has even suggested the club may not bring in a new centre forward at all.
The announcement this week that Aguero, City’s record goalscorer, is to leave the Etihad Stadium at the end of the season has intensified speculation linking the club with Borussia Dortmund’s prolific Erling Haaland.
The Nigerian, who left City in 2017, has scored seven goals in his last four games for the third-placed Foxes.
“Incredible,” said Guardiola when asked about Iheanacho at his pre-match press conference. “The quality was there.
“He was a young player (here) but with Gabriel and Sergio we didn’t have much space. He is a fantastic person. We had a good relationship. I’m delighted it’s going well lately.”
City need 14 points to mathematically secure the title but Guardiola is well aware of the dangers of Leicester, who won 5-2 at the Etihad Stadium in September.
He said: “Since Brendan Rodgers took over the team they have been incredible. Last season they had an incredible chance to qualify for the Champions League and they are in an incredible position again.
“They are a serious team, a contender every season, with a top manager and top players. It is a big challenge for us.”