London - If Manchester United are to claim a seventh successive Premier League victory and condemn leaders Chelsea to a first home league defeat of the season their manager Louis van Gaal must solve another complex injury puzzle.
Third-placed United will arrive at Stamford Bridge on Saturday on a run of six league victories but last weekend's 4-2 derby demolition of champions Manchester City came at a cost.
Midfielder Michael Carrick has a calf problem, Daley Blind sustained an ankle injury in a hefty challenge from City captain Vincent Kompany and defenders Phil Jones and Marcus Rojo also picked up knocks.