Rooney's double after half-time in Tuesday evening's 3-2 Champions League victory over AC Milan at the San Siro were his first European goals of the campaign.
"When you look at the way he is performing at the moment he must be regarded amongst those players at the highest level," said Ferguson.
The brace took Rooney's tally for the season to 25 and more importantly allowed United to take a potentially vital advantage from the first leg of the last-16 clash.
After years of playing second fiddle to Cristiano Ronaldo, Rooney is now emerging as the talent it was always felt he would become when he burst on to the scene as a raw teenager at Everton.
And, as Ferguson pointed out, it was too much for Milan's ageing defence.
"His second-half performance tonight carried on the form Wayne has been showing recently," added Ferguson after the victory.
"He is in absolutely devastating form. They could not handle him. They just could not handle him in the second half. I thought he was marvellous."