"He is an exceptional player", Guardiola said.
"Aguero's numbers speak for themselves - he is unbelievable", Guardiola told the BBC. I am so happy for him because we need him and his goals.
"We have found our game, we can make short passes and we have a lot of energy from our full backs".
Table-toppers Manchester United and Manchester City, now second on goal difference, both have 10 points from their opening four Premier League games.
He's already scored five goals this season and he has a chance to really impress further this season with Leipzig making their first appearance in the Champions League, a real test of his credentials for one of the "big" clubs.
Swansea brought Tottenham back to earth in a scoreless draw at Wembley, three days after Spurs tore apart Borussia Dortmund.
Newcastle United recorded a third successive win by beating Stoke City 2-1 at St. Jame's Park.
Violence against Rohingya Muslims in Myanmar must stop
One Rohingya man said his village of Rashidong had been attacked six days earlier by Myanmar soldiers and police. Activists say more than 100 villagers, women and children among them, have been killed by security forces.
The second goal of his magnificent hat-trick today marked his 200th league goal in Europe. Below is a ratings form for you to fill out with how you rate each Manchester City player's performance. Eleven against 10 was much better but sometimes it's not easy to play 11 against 10, and we did it so well. Last season, they all had to work out the kinks as they transitioned into Pep Guardiola's system.
Lukaku has scored six goals in six games for United, having managed 71 goals for Everton in the past three seasons, but the Belgian said he does not feel under any pressure after his move.
Watford finished 17th the previous year, but have improved heavily and will look to contend in every match this year.
Southampton registered a 1-0 victory over Crystal Palace at Selhurst Park in the early Saturday kick-off.
Hodgson has been out of management since Euro 2016, where his England side was eliminated by minnows Iceland.
Watford now sit in a Champions League qualification spot, and while it is early in the season you never know what could happen, should the side continue its impressive streak.
Tottenham is still looking for a first domestic victory of the season at its temporary Wembley Stadium home. A late goal by Sevilla last Wednesday kept the Reds from taking home three points in the Champions League.
Christian Atsu's 19th-minute opener was cancelled out by Xherdan Shaqiri shortly after the restart, and the same player was denied a second only through an excellent save by Rob Elliot.