Chelsea manager Jose Mourinho believes the current Blues squad are not able to match Arsenal "invincible" record despite an impressive start to the campaign.
Ten years ago, Arsene Wenger side secured the Premier League 2003-2004 without losing a single match.
With Chelsea leading the Premier League after an impressive start to the season, securing five victories and just one draw from the first five games, some pundits have claimed the Blues can eventually emulate that Wenger side.
However, when asked about that in the press conference ahead of the London derby against Arsenal on Sunday, Mourinho said: "That is something that happens once in a lifetime"
"I don't see in modern football, with the competitiveness of this Premier League, that one team can be champion without a defeat."
At the same time, Mourinho does not expect Chelsea to secure another vast victory against the Gunners on Sunday after last season's 6-0 victory.
"The 6-0 happens every 50 years, occasionally. What happens in the past is the past. It's a difficult match against a good team," he said.
"It doesn't matter what they try to do, they can have many different approaches. I always expect [to win] every game. Nothing changes in relation to that."
Cesc Fabregas will face his former club Arsenal for the first time since his move to Stamford Bridge.
Speaking about the expected reception, Mourinho said: "If 40,000 Blues fans want, nobody will listen to 3,000 red fans.
"It depends on the club culture. You could see the Chelsea fans with Lampard. It depends. Fabregas was made at Arsenal. Every game, no exception, [Fabregas] is playing well. I couldn't be happier with the moment he decided to join. He's our player, that's what matters."
Meanwhile, when questioned about last season's confrontation with Wenger, he said: "That was as a consequence of something. It wasn't my first option.
"Me against Arsene Wenger, I never had the pleasure to play against him one-on-one, it is always between Chelsea and Arsenal. That doesn't play an important part of Sunday's game."