Robin van Persie is upset with David Moyes for forcing him to play while he is still injured, according to the Times.
The Dutch striker is carrying toe and ankle injuries, and was absent from Manchester United's 1-0 Champions League win over Real Sociedad last month.
Van Persie is believed to be receiving pain-killing injections for his injuries, and returned to score in the Red Devils' 3-2 victory over Stoke last weekend.
The Times report that the Manchester United ace is unhappy with Moyes for forcing him to play through the pain barrier and will demand showdown talks to resolve the issue.
He is also said to be concerned that playing with injections could cause him long-term problems.
Speculation has been rife since Moyes succeeded Sir Alex Ferguson that Van Persie's relationship with his new boss is strained.
The pair were seemingly spotted arguing during training this week, while previous reports have suggested that Van Persie is unhappy with Moyes's training methods.
Manchester United take on Fulham at Craven Cottage later today, and Moyes insists the former Arsenal striker is fit to start.
He said: "Van Persie has been fine. He's trained well and worked quite well this week so hopefully he will be okay."