Muhammad Ali was on the short list to play Superman in 1978 film

Boxing legend Muhammad Ali and veteran actors Al Pacino and Dustin Hoffman were on the short list to play Superman in the 1978 film, producer Ilya Salkind has said.

According to the Hollywood Reporter, Salkind made the revelation on the commentary track in the newest edition of the film which was recently released to coincide with its 40th anniversary.
"One of the conditions with DC Comics was I had to make a list of actors to play Superman that they had to approve.
"I had a made a list that was absolutely hilarious because they had approved people like Cassius Clay then, they had approved Al Pacino, they had approved Dustin Hoffman. They had approved them, they could play Superman," Salkind said. 
Christopher Reeve played the iconic DC superhero, but Ali and Superman teamed up in the comics to defeat an alien invasion of Earth.
The comics titled "Superman vs Muhammad Ali" also released in 1978.
Salkind shared the casting process was "complex" and confusing at times. 
"One side, they were extraordinarily protective (of the character's image) and on the other side, they weren't so aware of reality because as much as Dustin Hoffman is a fantastic actor, I don't think he would have been a great Superman. Perhaps he could have been." 
Hoffman was also considered for the role of Lex Luthor. 
"We met with Dustin at Cannes... We had dinner with Dustin to play Lex Luthor, which would have been pretty exciting. But it didn't work out," Salkind said. 
The role went to Gene Hackman.