Although recent films like Million Dollar Baby and Cinderella Man are providing competition, the Rocky quintet still stands as the Mecca of boxing movies. It is common knowledge that Sylvester Stallone got the idea for the first film while watching a closed-circuit broadcast of Muhammad Ali’s bout with Chuck Wepner. When Stallone saw the “Bayonne Bleeder,” a career journeyman, knock Ali down in the ninth round, the inspiration for Rocky came to him.

Stallone did not cast Wepner in any of the Rocky movies. If Sly had, he may not be facing a lawsuit from the “Bayonne Bleeder.” However, many boxers have made the jump from the squared circle to Rocky-land. Some of the crossovers were obvious, some were hard to spot, and some did not make the cut because they broke two of Stallone’s ribs. More on that in a minute.

The first and most notable cameo came in the first Rocky when “Smokin’” Joe Frazier made an appearance in the bout between Rocky and Apollo Creed (Carl Weathers). In the movie, Frazier shakes Rocky’s hand and walks over to Apollo, who jokingly says, “You next Joe. You next.”

“I had such fun, and he [Frazier] was such a game participant,” said Weathers. “He went with the whole thing so I could just kind of go crazy. You know none of that stuff was written. We just had fun with it.”

Frazier, who has plenty of experience playing off boisterously loud fighters, obviously had no problem improvising on Weathers’ antics. By the time that scene was shot, improvisation was the theme of Rocky’s production. The original film was shot on a shoestring budget, and many of its quirky moments like the baggy robe and the poster of Rocky wearing the wrong shorts were actually production mistakes that had to be dealt with on the fly.

Frazier’s appearance was no different. The movie takes place in Philadelphia so it seems only fitting when “Smokin’” Joe, the city’s favorite son, shows up. However, director John G. Alvidsen wanted the scene to have the celebrity-filled feel of a real heavyweight championship bout.

“We wanted to get as many ex-champs to be at the final fight as we could, but nobody had heard of us, and the only guy that showed up was Joe Frazier, which worked to our advantage because he was from Philadelphia,” says Alvidsen.

Frazier was also considered for the role of Clubber Lang (Mr. T) in Rocky III. By this time, Stallone had become a box office sensation and had developed the muscular physique for which he is known. Naturally, he must have felt that these were the necessary qualifications to take on an actual heavyweight contender.

“Smokin’” Joe only received brief consideration, but one heavyweight who received an actual audition was Earnie Shavers, one of the most powerful punchers in boxing history. Shavers scored knockouts over Jimmy Young, Ken Norton and Jimmy Ellis. His first title shot against Muhammad Ali prompted Sports Illustrated to openly urge the Greatest to retire. In his second title shot, he sent Larry Holmes to the canvas before eventually being knocked out in the eleventh round.

In the audition, Shavers gave Stallone a taste of his power, and it likely cost him the part.  Here’s how Shavers told it to ESPN a few years ago:

“Got a call and went out to try out for this part in Rocky, the Mr. T Rocky, I think. Got out there and got put up in a good hotel for a change. Then got in the ring with Mr. Stallone. He's not a real tall fellow, is he? Well, it don't matter. Anyway, we were circling; I was pulling my punches. He said, 'Don't hold back, Earnie. Hit me.' I said, 'I can't do that, Mr. Stallone.' I could've, but I wanted that job, and I didn't think that would help me get it. But he kept on pushing me, saying, 'C'mon, show me something,' and sort of hitting me, sort of. Finally, I said, 'OK,' and I give him a little one under the ribs, where the livers of boxers are. Don't know about actors. If they got livers, they probably are in the same place.

Anyway, Mr. Stallone called time.  He didn’t say nothing, just kinda doubled over a little bit and sort of just waved his hand — and then somebody helped him out of the ring, and to this bathroom or somewhere, and he sent word out later that they couldn't use me. It was like what they call an audition, and I guess I blew it.”

Stallone did actually take on a real fighter two films later in the forgettable Rocky V, although this time around he watched the audition of Tommy Morrison from outside the ring. Stallone caught many of Morrison’s bouts on ESPN and decided he would be perfect for the role of Tommy Gunn.

“Stallone got a hold of Bill Cayton, my manager,” says Morrison, “and Cayton and I flew out to Los Angeles. We went to the screen test, and then I went back home. About a week or ten days later, Stallone called and left a message on my answering machine telling me that they were going to use me and congratulated me.”

Morrison, a great grand nephew of John Wayne, was actually so well received as an actor that he received a three-movie contract when he performed in the fifth Rocky, but he was so busy with boxing that he actually let the contract expire.

On a final note, one other famous fighter appeared in the Rocky series as well, although he was little hard to spot. In Rocky II, Mickey is trying to help Rocky develop speed so he puts him in the ring with a smaller quicker fighter.

This is before Adrian goes into the coma, so Rocky is a little sluggish and preoccupied. The little fighter schools the “Italian Stallion,” and Mick gets mad. Mickey should have cut him a little slack though. For that little fighter was none other than Roberto Duran.