EXCLUSIVE: Jackson Tour Director Kenny Ortega Calls Michael "The World's Greatest Performer"

Kenny Ortega, the famed director/choreographer who was directing Michael's upcoming This Is It concert tour, was devastated at the news of his friend's death.

"Michael was a dear friend and a consummate professional," Ortega told RadarOnline.com exclusively.  "This was the most exciting collaboration of my life with a man who has inspired me like no other. He will be deeply missed."

"I am terribly sad. We had a 25 year friendship," added Ortega, whose credits include all the High School Musical films and the upcoming Footloose. "This is all too much to comprehend. This was the world's greatest performer and the world will miss him.

My heart goes out to his family and fans."