As we know, Aguero bagged a hat-trick and De Bruyne weighed in with a trio of assists, too.
Having coached Lionel Messi as the Barcelona superstar and Cristiano Ronaldo began their domination of the Ballon d'Or a decade ago, Guardiola was unequivocal when asked whether his 26-year-old midfielder was at a level to be considered for the prestigious individual prize.
While De Bruyne himself said it would be "beautiful" to win the award, he said he was fully focused on claiming team success.
It seems like things have changed.
"He is not (just doing it in) one game", he said.
Matt Ritchie's first goal of the season was enough to keep the three points on Tyneside, effectively ending United's already farfetched title hopes.
Pep Guardiola hailed Sergio Aguero as an "authentic legend" of Manchester City after his four second-half goals continued the club's emphatic march towards the Premier League title with a 5-1 thrashing of Leicester on Saturday night.
He is the Premier League's best player, even though he continues to be pushed by the likes of Mohamed Salah and Harry Kane as well as some of his team-mates, including David Silva, who has returned to training ahead of the FC Basel game. Considering Messi and Ronaldo's failure to win a World Cup, a victory in Russian Federation would surely make de Bruyne stand out. In Premier League, on the other hand, there are several top clubs able to win the title.
"The way he's played it's hard to find one [a player like him] in Europe".
After surpassing Fernando Torres and Daniel Sturridge to become the fastest Liverpool player to score 20 goals in the Premier League against Tottenham Hotspur, he equalled Robbie Fowler's record against the Saints. The team's previous best run was to the semifinals in 2016. The Belgian global is one of the Premier League's most creative players, with a few managers including Pep Guardiola calling him the best player in the English league at the moment. The Belgian is playing in a deeper central-midfield role, where he can influence games more with his passing, energy and reading of the game.
On extending his deal, De Bruyne said: "I feel very good here and I am very happy".
"To be fair, when I am busy playing football I don't care".
"It is not easy because they had five guys at the back, four in front - there are nearly no spaces".