John Terry believes Jose Mourinho's record-breaking Chelsea side from 2004-2006 would beat Pep Guardiola's Manchester City.
City lead the Premier League table by 11 points after just 18 games and have dropped just two points across the entire campaign, drawing 1-1 with Everton in their first home fixture of the season.
Guardiola's men claimed their 16th successive top-flight victory on Saturday, thumping Tottenham 4-1 at the Etihad, to become he first team since Wolves in 1953-54 to beat Arsenal, Chelsea, Liverpool, Manchester United and Spurs in the league before Christmas.
As such, the current City side have been compared to a number of the greatest teams the English top flight has ever seen - Arsenal's double-winning outfit from 1998 and indeed their 'Invincibles' from 2003-04, or city rivals United's Treble-winners from 1999.
Mourinho's early Chelsea sides have also been brought into the conversation, having claimed consecutive Premier League titles in 2004-05 and 2005-06, and breaking the record number of points won in a season with 95 - a landmark which still stands.
And Terry, Blues captain for both seasons, believes the team constructed at Stamford Bridge during the Portuguese's first stint in west London would have beaten Guardiola's runaway leaders.
When asked if Chelsea would beat them, Terry told Sky Sports: "Yes, yes. I would say 2004/05 or 2005/06, those first two sides when Mourinho arrived at the club.
"We were never afraid to say: 'They'll have more possession than us', but we were set, comfortable.
"The full-backs [William Gallas and Paulo Ferreira] would always go up the pitch, and [Claude] Makelele would always sit, which was great for us centre-backs.
"But we had great legs, great power, and we had the big man up front. Didier [Drogba] made such a difference. We had that ball into Didier, and he could hold it up, with the runners off him [Damien Duff and Arjen Robben] and [Frank] Lampard would be box-to-box game after game."