One of the season's most hotly anticipated games is almost upon us, with City and United contesting the Manchester derby on Sunday lunchtime.
With points and pride at stake you can expect a game full of blood and thunder, and that could leave the referee with some big decisions to make.
But he's not the only one who's decision making will impact the outcome of the game, first the two managers must get it right with their team selection.
As the home team, and reigning Premier League champions, the pressure will be on Manuel Pellegrini's side to arrest their recent slump and take maximum points from the red half of Manchester.
That task was made harder by the news that Spanish playmaker David Silva will miss the game with a knee injury, meaning Pellegrini will need to find some creativity from elsewhere.
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As if scripted, Silva's injury has coincided with the return of City's other creative force in midfield - Samir Nasri.
The Frenchman made his comeback from a month out on Wednesday night, and will now surely take over from his fellow attacking midfielder.
Having Nasri available to step into Silva's shoes will come as a boost to Pellegrini, although City fans would have liked to have seen the pair of them causing trouble for United's vulnerable defence.
Another headache for Pellegrini is the centre of his defence, although unlike creative midfielders, he has plenty of options at his disposal here.
Both Eliaquim Mangala and Martin Demichelis have been given the opportunity to partner Vincent Kompany this season, and both have impressed and disappointed in equal measures.
On debut against Chelsea, Mangala made a fantastic start to life in the Premier League, but his form has struggled since.
Pellegrini must now decide if he wants to back the experience of Demichelis, or the potential of Mangala, either way the chosen one will have to be at his best to stop an attack that could contain Robin van Persie, Wayne Rooney and Radamel Falcao.
It's not just personnel that will impact the result, but also the tactics employed by the respective managers.
The biggest decision for Pellegrini in this aspect of his team selection will be whether to go with one on two up front, with Sergio Aguero almost certain to get the nod either way.
Should be play the Argentine as a loan striker he could deploy the Brazilian pair of Fernando and Fernandinho in front of a back four enabling Yaya Toure a free role in midfield.
Alternatively, Pellegrini may decide the best form of defence is attack, and chose to partner Aguero with Edin Dzeko, who scored twice when the two teams met at the back end of last season.
With United's defensive having come under scrutiny this season, especially during the 5-3 defeat to Leicester, City fans will expect their team to attack from the off, giving Dzeko a chance to recreate last season's heroics.
Manchester City: Predicted line-up
Hart; Zabaleta, Kompany, Demichelis, Clichy; Milner, Fernando, Toure, Nasri; Aguero, Dzeko
Manchester City 2-1 Manchester United