Manchester City manager Roberto Mancini has earmarked his side's clash with Manchester United as this season's title decider.
The top two face one another on 30 April at the Etihad Stadium, and in light of the Citizens' loss to Swansea City and United leapfrogging them with a win over West Brom on Sunday, the fixture has gained even greater significance.
"Today was not critical. I think this championship will be decided with three games to go," the Italian told BBC Sport.
City's loss in Wales was their fourth defeat in the league and, coupled with United's win, has seen the Reds go one point ahead of their neighbours.
Scott Sinclair had an early first half penalty saved by Joe Hart but substitute Luke Moore headed in the winner from Wayne Routledge's cross, with less than 10 minutes remaining.
United defeat City in the season's first Mancunian derby:
Michel Vorm made two good saves following the opener, while Micah Richards had a goal correctly disallowed for offside in the dying embers as City laid siege on the Swansea goal.
On top of a bitter defeat, the Blues' first half withdrawal of Gareth Barry for Sergio Aguero was met with visible disdain by the England international, while Mario Balotelli and Yaya Toure had a half-time spat in the tunnel.
"Gareth has had a problem for three weeks," said Mancini. "Gareth has a problem, I don't know where. It is a small injury.
The April fixture will be the fourth Mancunian derby of the season. United came from 2-0 down at half-time to win 3-2 in the Community Shield at Wembley in August, but two months later City walloped their rivals 6-1 at Old Trafford.
Most recently, the two teams met in the FA Cup in January, when 10-man City rallied from 3-0 down after the interval to reduce the deficit to 3-2, but a startled United held on for the win.
City trounce United 6-1 at Old Trafford: