Here is a run-down of the key battles...
Robin Van Persie vs David Luiz
The Dutchman has made a mockery of concerns about his form with six goals in his last four games, and he will undoubtedly be the key man in Manchester United's attack on Sunday once again. Luiz has become a real leader for Chelsea under Rafa Benitez, and the Spaniard will be hoping for another composed display from his centre back to keep Van Persie and United at bay at Old Trafford.
Phil Jones vs Juan Mata
Jones has been impressive for United in recent weeks, playing either in the defence or pushed into a midfield role. Alex Ferguson might be tempted to opt for the latter on Sunday to add some extra protection for his back four in the face of Chelsea's array of attacking midfielders, and Jones could be used to combat Juan Mata in particular. The Spaniard has been wonderful for Chelsea all season, and if he is marshalled out of the game by Jones, Chelsea's attack will lose much of its potency.
Michael Carrick vs Ramires
Pulling the strings in United's midfield all season, Michael Carrick has enjoyed an excellent year at the heart of their title win. John Obi Mikel will likely sit deeper to help his defence deal with the home team's forwards, meaning Ramires will need to push further up to try and cut off the supply from Carrick. Carrick will also have a role in tracking the Brazilian's burst from midfield, with Ramires demonstrating his eye for goal in Chelsea's last trip to Old Trafford by scoring the equaliser in their FA cup draw.
Rafael vs Eden Hazard
Although Mata is still the key player in Chelsea's team, Hazard has become almost as important as the Spaniard this season, with his direct style a constant threat in and around the opposition area. Rafael will probably be the full back tasked with keeping Hazard at bay, and he will need to track the Belgian carefully as he moves around the final third. Hazard also has a defensive job to do, helping his full back out when Rafael joins the attack.
Antonio Valencia vs Ashley Cole
None of United's wingers have hit their best form this season, meaning Ferguson could opt for a team without either Nani or Valencia if the fancy takes him this weekend, However the Ecuadorian is likely to start on the right, and if he can recover some confidence, he will be a threat if Cole is left isolated in Chelsea's attacking system. Valencia always does his duty at the back too, and he could be important in doubling up against the likes of Eden Hazard.