Arsenal came from behind to beat Chelsea 2-1 in a London derby, preserving their perfect start to the Premier League season and strengthening their early title credentials.

The reigning champions have taken nine points from three matches and conceded just once. They had already defeated Coventry City and Aston Villa before overcoming Chelsea, who took the lead through £117 million signing Morgan Rogers in the second minute.

Kai Havertz equalised before half-time, and captain Martin Odegaard completed Arsenal’s comeback in the 50th minute. The result gave Arsenal their first major test of the campaign against a Chelsea side that has spent close to £350 million since the end of last season.

“ Our mentality is to keep fighting. We have shown that many times,” Odegaard said. “We never want to concede early, but the reaction is top. We got our reward in the end and the response was brilliant.”

Odegaard has scored three goals in four appearances in all competitions this season, after scoring once in 36 appearances last term. Former Manchester United and England player Ashley Young said the midfielder’s form would be important for Arsenal.

“He’s just a joy to watch,” Young told BBC Sport. “He’s exciting when he gets on the ball, he’s allowing other players to get on the ball.”

Havertz said Odegaard was back to his “very best” and would help Arsenal significantly during the season.

Former Premier League winner Chris Sutton said Arsenal remained ahead of their rivals despite significant spending elsewhere in the league.

“They’re such a powerhouse,” Sutton told BBC Sport. “Chelsea are a good team, but Arsenal always find a way to win.”

Arsenal have won their opening three top-flight matches while conceding fewer than two goals for only the third time. The other occasions were in 1924-25 and 2003-04, when they went the season unbeaten. They have also won eight league matches in a row dating back to last season.

Arsenal’s next listed league match is away at Sunderland. Before that, they begin their Champions League campaign at Napoli.