Manchester City, Premier League champions in 2012 and 2014, went to the top of the table with a 3-1 victory over West Ham United on Sunday.
Superior goal difference took them above Chelsea and neighbours Manchester United, who have also won their three opening games.
Having scored twice in the first 18 minutes through Raheem Sterling and Brazilian midfielder Fernandinho, Pep Guardiola's team appeared set for an easy three points, only to be pegged back as the London side improved after halftime.
Michail Antonio reduced the deficit in the 58th minute but Sterling scored his second goal in stoppage time from an acute angle.
City could have leading scorer Sergio Aguero banned for the derby match against United next month if retrospective action is taken after he appeared to swing an arm at West Ham's Winston Reid, who had to go off after taking a blow to the throat.
"I did not see the incident," Guardiola told reporters and neither did West Ham's manager Slaven Bilic.
"Reid got a little injured so we took him off," Bilic said.
For his third league game in charge of City, the former Barcelona and Bayern Munich manager again picked Willy Caballero in goal rather than Joe Hart, and the Argentine was not troubled for almost an hour until Antonio's unexpected intervention.
In the meantime, Sterling scored his first goal of the season following a fine move and Fernandinho added his first in the league since the same weekend last year.
He was left completely unmarked to head in Kevin de Bruyne's free kick as goalkeeper Adrian glared at his defence.
Bilic's side, again weakened by injuries and unable to use new loan signing Simone Zaza from Juventus, employed three centre halves plus wing backs, but defended poorly against City's fluent attacking.
In the second half, Bilic pushed Antonio further forward and he headed in a cross by Arthur Masuaku.
City briefly looked nervous but in the last few minutes David Silva hit a post and Sterling made the victory safe.
"You have to win 3-0 or 4-0 to think the game is over," Guardiola told Sky Sports.
"We played a good game. Our fans enjoyed it and we are happy.
"I don't know how many shots we had but the performance in general was real good."
West Ham stayed 12th in the table after their second defeat.
"I wasn't happy at halftime," Bilic said.
"I asked the guys to show character and spirit and a different mentality which they did. Praise for the team for the second-half performance.
"A few will be back after the international break."