Pep Guardiola's City have built an eight-point lead following an unbeaten start to the season that has included 13 straight victories - equalling the record for the longest winning run in a single Premier League campaign.
Not to be completely outdone, however, Jose Mourinho’s Manchester United have equalled a historic club record by remaining unbeaten at Old Trafford for 40 matches in all competitions.
And with former Barcelona boss Guardiola and ex-Real Madrid manager Mourinho having developed a fierce rivalry during their time together in Spain, Sunday's meeting promises to be one to savour.
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The last team to beat United at home were City in September, 2016 and a repeat performance would leave the club, once derided as "noisy neighbours" by former United boss Alex Ferguson, 11 points clear at the summit.
City have been playing some exhilarating football this campaign with coach Guardiola's style of play, which served him so well at his previous clubs, bringing the expected rewards after a disappointing lack of consistency last season.
Yet while United have suffered two defeats on the road - to Huddersfield Town and Chelsea - they too have looked like champions at home.
The 40 games unbeaten have included 29 wins and 11 draws with 85 goals scored and just 17 conceded.
This season's Premier League record at Old Trafford is played seven, won seven - 20 goals for and just one against.
Mourinho, however, will be without his key French midfielder Paul Pogba, who starts a three-match ban following his red card in Saturday's crucial 3-1 win at Arsenal.
United have produced their best football when they have had Pogba and Serbian anchorman Nemanja Matic on the field together and the former Juventus midfielder will be sorely missed.
Given the gap between the two clubs in the table, it will be intriguing to see if Mourinho maintains his habit of playing defensively against title rivals, a tactic which has been much criticised following the goalless draw at Liverpool in October.
Pogba, however, says United will approach the game in a positive fashion.
"We want to win. We need to win as well. They need to win because they know that we are behind and we are closing and closing," he said.
"If I didn't believe that (we can win it), I'd stop playing football now," he added.
United's Swedish striker Zlatan Ibrahimovic should be fit to feature at some stage in the game but defender Eric Bailly remains sidelined.
(Reporting by Simon Evans; Editing by Toby Davis)
