Gullit was unimpressed by United's display for their draw with Champions League opponents Benfica last week
"Benfica played well, daring and aggressive," said Gullit. "You see even Manchester United struggle and are very dependent on Wayne Rooney. They lack a creative midfielder like Sneijder and he's someone who can take them to another level.
"Furthermore, United miss Edwin van der Sar. They miss him organising things in front of him. Ferguson recognises this."