Mike “King” Kelly signed in 1891 to captain the new American Association club in Cincinnati and joined the Boston Reds in that league after Cincinnati released him in August. But after just eight days with the reds he jumped to the Boston Beaneaters of the National League.
The New York World called Kelly’s action, a “Hard blow to the Association.”
Kelly jumped as representatives of the two leagues were engaged in a “Peace conference” at Washington’s Arlington Hotel.
The Baltimore Sun said:
“The action of Kelly had the effect of breaking up pending negotiations, for the time being at least, the Association representatives leaving the conference when the League men refused to give them any assurance that would be compelled to remain with the Reds.”
Mike “King” Kelly
The Chicago Evening Post claimed to have the story behind Kelly’s move, and concluded which team he “morally” belonged to:
“It is held by persons who urge that they know that the King signed a Boston (NL) contract and accepted advance money two months before (he signed with Cincinnati). The incident happened at the Fifth Avenue Hotel (in New York) last winter during the conferences that finally ended in the dissolution of the brotherhood. One night Kelly came into the hotel ‘broke,’ having spent the afternoon and his roll at Guttenberg.”
Guttenberg was a racetrack located across the river from Manhattan, in what is now North Bergen, New Jersey—open from 1885-1893, it was at the time, the only track that held winter racing in a winter climate.
The Evening Post said Kelly found “His old friend, Director (William) Conant of the Boston (National League) triumvirate.” Kelly said:
“’Bill, I’m dead broke. Can I touch you for a few hundred?’
“’I don’t know Kel’ was the reply. ‘I guess, though, you can have the money if you’ll sign a contract to play ball with me.’”
The paper said the two went upstairs to Conant’s room:
“A League contract was produced and a roll of greenbacks was spread before the King’s beaming countenance. ‘Kel’ picked up the money, signed the contract and then put both the money and the document into his pocket, with the cool remark:
“’When I get ready to return this contract to you, Bill, I will. See?’
“And with that he walked of.”
The Evening Post said Kelly initially signed with the Boston Reds after his release from Cincinnati because he tried to borrow more money from Conant:
“Conant refused to accommodate him unless that contract was handed over. But ‘Kel’ was obstinate, and not getting the money from Conant, went over to (Charles A.) Prince, who gladly gave it to him.”
But, Kelly quickly decided to honor the “contract” he signed with Conant:
“These are facts, every one of them, from which it must be inferred that Kelly was really under contract morally to the Boston League people all the time that he played with Cincinnati and the Boston Reds.”
The Beaneaters were in second place, four games behind the Chicago Colts, on the day Kelly jumped, August 25. Kelly only appeared in 16 games and hit just .231, but Boston went on a tear, winning 30 of their last 40 games after the King joined the club, and overtook Chicago for sole possession of first place on September 30, and won the pennant by three and a half games.
Baseball History Daily 
I could see Kurt Russell playing him in a movie.
A King Kelly movie would be incredible.