Harry Maguire leaves Villa Park wearing a protective boot after being helped off the field by the club doctor due to his injury.
He was assisted by a team doctor before the whistle blew.
Maguire’s knee appeared to be locked during a Villa set piece just before halftime.
The back of his sock was completely torn, revealing a large hole that exposed his entire calf as keeper Andre Onana helped him to the sidelines.
Maguire was holding his calf before being aided off the field by three members of Manchester United’s medical staff after referee Robert Jones’ whistle.
The Telegraph reports that the England center-back left Villa Park in a protective boot, leaving Erik ten Hag worried about his fitness.
Maguire’s counterpart, Jonny Evans, also seemed to be struggling in the first half after a crunching challenge on Leon Bailey but went on to win Man of the Match.
Maguire and Noussair Mazraoui were subsequently substituted at halftime, with Matthijs de Ligt and Victor Lindelöf brought on as replacements.
Maguire also received a yellow card for leaning into Ollie Watkins’ face with his arm in the 36th minute and will now undergo tests to determine the extent of his issue.
The 31-year-old missed Euro 2024 due to ongoing calf problems.