Jose Mourinho & Manuel Pellegrini: The latest great rivalry?
Manchester City's meeting with Chelsea at Etihad Stadium was a collision of the Premier League's two current superpowers.
The game ended with honours even between the two teams likely to be contesting the title when it reaches its decisive stage, and the 1-1 draw gave both City manager Manuel Pellegrini and Chelsea's Jose Mourinho an indication as to how their seasons may unfold.
Chelsea stay five points ahead of City and three points clear of second-placed Southampton - so what are the sub-plots that will accompany their fight for the title?
The new Fergie v Wenger?
Manchester City and Chelsea have the look of two clubs who will dominate the Premier League title race - and who will have a managerial rivalry to go along with it.
Sir Alex Ferguson's relationship with Arsenal manager Arsene Wenger in the "Pizzagate" years - which began when Ferguson was struck by flying foodstuffs hurled from Arsenal's dressing room in 2004 - only truly thawed once the Gunners were no longer deemed a serious threat to Manchester United's supremacy.
And when Liverpool briefly emerged as a possible danger to United, what had started as a cordial relationship between Ferguson and Rafael Benitez degenerated swiftly, culminating in a famous monologue from the Spaniard bemoaning the Scot's influence over officials and the game in general.
Do we have the natural succession in the barely-concealed contempt between Manchester City's Pellegrini and his Chelsea counterpart Mourinho?
The relationship was already fractured from the days when Mourinho succeeded Pellegrini at Real Madrid and appeared to scoff at the fact that the Chilean then went to Malaga to rebuild the next phase of an excellent coaching career.
And judging by their antics after Sunday's draw at Etihad Stadium, it is likely the pair will provide a running sub-plot to this season's Premier League title battle.
It was behaviour that did little credit to either man, who should have far more pressing issues to attend to as the season progresses.
Mourinho performed his usual trick of getting the City's manager's name wrong with references to "Pellegrino", while Pellegrini delivered a nonsensical barb about Chelsea playing like "a small team" - reviving memories of a Benitez insult aimed at Everton after a goalless Merseyside derby at Anfield.
The mischief of Mourinho is long in the making and is, according to his detractors, well-practised, but Pellegrini's reputation is that of the measured, quiet man.
Appearances can be deceptive, as those present when he lambasted the officials after last season's Champions League loss at home to Barcelona, and after last weekend's draw at Arsenal, will testify.
It is clear the Portuguese can get under his skin and you suspect Chelsea's manager may take the opportunity to indulge himself further should the stresses of the title race increase.
Lampard does Premier League a favour?
Frank Lampard's goal for Manchester City against the club he served with such distinction prevented Chelsea from opening up an eight-point gap over the Premier League champions, who are regarded as the team that will run them closest this season.
The advantage may not have been a deal breaker in title terms but would certainly have established an imposing lead with arguably Chelsea's toughest league fixture of the season out of the way,
The Stamford Bridge club have still made an outstanding start, despite losing their 100% league record, and hold a three-point lead over Southampton.
City are only five points behind and the suspicion remains that there is so much more to come from Pellegrini's team, who also showed great spirit and resilience to come back from a goal behind following Pablo Zabaleta's sending-off.
As for Lampard, what a moment it was for the 36-year-old, who attained legendary status at Chelsea after becoming their all-time record scorer with 211 goals in 648 appearances before leaving and securing a move to New York City FC.
The former England midfielder is on loan at City until January and demonstrated that plenty of his footballing faculties remain intact as he punished Chelsea for failing to track him into the area with five minutes left, a volley expertly slid beyond Thibaut Courtois providing the evidence.
If there is one exception to the latter-day, and ridiculously overdone, habit of refusing to celebrate against a former club, Lampard scoring against Chelsea probably provides it.
He was understandably suffering mixed emotions as he turned away: a job completed with his trademark professionalism on one hand, while also respecting the Chelsea fans who gave him a rapturous reception throughout on the other, and who set aside their own disappointment to repeat the acclaim after the final whistle.
Lampard took the applause of both sets of supporters, but there was poignancy as he fell into the arms of long-time Chelsea team-mate Petr Cech in front of the travelling fans.
He will not be around when the Premier League title is decided, but Lampard has once again made his contribution.
A match made in heaven?
Manchester City captain Vincent Kompany confirmed he is in the elite bracket of the world's defenders with a magnificent performance in a fierce physical battle with Chelsea's Diego Costa.
And Martin Demichelis has done much better than he has been given credit for in recent months, playing a key role in City's title win last season and also playing in the World Cup final for Argentina when they lost to Germany in Rio de Janeiro.
But the partnership between Kompany and Eliaquim Mangala on Sunday was a glimpse of the long-term future at City and the fans will have loved what they saw.
Both big, quick, powerful and tremendous athletes, they were a formidable barrier and looked the identikit of what is required in the modern defender.
Mangala has had to bide his time after his £32m summer move from Porto, but the 23-year-old French defender looked the part from the first whistle against such a dangerous Chelsea attack.
Chelsea show old steel
Jose Mourinho's side have been accused of sacrificing some of their trademark defensive steel in exchange for the attacking options offered by the arrival of £32m striker Costa and midfielder Cesc Fabregas.
|Chelsea's goal came from their first shot on target||Eight of Chelsea's last nine league goals have come in the second half|
|Man City keeper Joe Hart made his 200th Premier League appearance||Yaya Toure has not scored or assisted a league goal so far this season|
Here at Manchester City, the steel at the back made its return as Chelsea stood firm in the face of City's attacks and showed again that they have a worthy goalkeeping successor to Cech in Courtois, an authoritative and commanding figure.
Chelsea have shown their potency in attack but Mourinho will have been reassured by how his defence and goalkeeper performed against such dangerous opponents.