Erik ten Hag has disputed suggestions Manchester United's training sessions are too intense amid their latest injury crisis.
Centre backs Victor Lindelof (hamstring) and Lisandro Martinez (calf) have been ruled out for a month and Martinez, who has appeared in only 11 of United's 41 matches this season, suffered the setback in training on Tuesday.
Casemiro, who never had a muscular injury during his eight-year career at Real Madrid, is believed to have partly blamed the intensity of United's training sessions on his hamstring problems this season.
The 32-year-old was sidelined for two-and-a-half months with a hamstring injury and a recurrence of the issue caused him to miss the FA Cup quarter-final victory over Liverpool last month.
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