Actually, it was his 5th world title, but since the New Zealand / Singapore title change in 1984 with Harley Race was not yet recognized at that time, Flair's win over Rhodes in St. Louis was recognized as his 4th in 1986.
Tully Blanchard had attacked Rhodes before a match two days earlier in Kansas City, KS and that injury set up Flair's opportunity to regain the Big Gold belt this night in St. Louis - - - 30 years ago!
