Conversation so far:
Why did Superstar Billy Graham return to the WWWF?
Graham returned to the WWWF in April 1977 after an agreement with promoter Vincent J. McMahon
What was Superstar Billy Graham's agreement with McMahon?
How did people respond to Superstar Billy Graham's return?
What else happened to Superstar Billy Graham during 1977-1981?
Graham defeated Bruno Sammartino for the WWWF Heavyweight Championship on April 30, 1977.
What happened after Superstar Billy Graham defeated Bruno?
Graham defeated Bruno Sammartino for the WWWF Heavyweight Championship on April 30, 1977, in Baltimore, Maryland. Graham held the title for nine and a half months.

Question: Who took the title after?
Self-contained rewrite: Who took the WWWF Heavyweight Championship title after Superstar Billy Graham in 1977?