Wayne Rooney converted the chance from 12 yards and the Red Devils went on to win the encounter 4-0.
However, McLeish believes that his player was the innocent party in the incident that set United on their way to victory.
"It was a soft penalty because Ciaran Clark has tried to pull his foot away and Ashley Young has gone looking for his leg," McLeish told BBC Sport. "He won a penalty that I don't think it was derserved."
The loss has left Villa 15th in the Premier League table.