Jack Mcauliffe, who retired as undefeated lightweight champion of the world in 1896, once had a monkey that rode his neck when he did roadwork.
Twenty miles was customary in those days - they trained for finish fights - so the monkey and McAuliffe saw a lot of territory together.

"The Monk would hold on with his legs around my neck, and if I stopped too fast he would grab my ears to stop from falling off" McAuliffe said years later.
*'The Monk' (as McAuliffe referred to him)

McAuliffe in his glory had been a great friend of John L. Sullivan and of a bantamweight named Jack Skelly from Yonkers. The three were engaged to perform in a Salzburg festival of the sweet science promoted by the Olympic Club of New Orleans in September 1892.
On September 5, McAuliffe was to defend his lightweight title against Billy Myer. On the 6th, Skelly would try to win the featherweight championship from the incumbent George Dixon. And on the third climatic night, the great John L would annihilate an upstart from San Francisco named Jim Corbett.

"I thought the monkey would bring us all luck" McAuliffe said "He started good. When I knocked Billy out in the fifteenth the monk was up on the top rope as the referee said 'Ten!' and hopped off on to my shoulder before the man got my hand up. I took him and threw him in the air and caught him, I was so happy...."Oh, you jewel of a monkey!" I said, and when I was on the table after the fight he played in the hair on my chest like I was his brother.....Then Skelly fought Dixon, and when Dixon knocked him out I thought I noticed a very peculiar look on the monkey's face, like he was glad to see Skelly get it. I said to myself 'I wonder who you are.' I gave him the benefit of the doubt, but when Corbett stopped Sullivan, I grabbed the monkey by the neck and wrung it like a chicken. I've often felt bad about it since. God help me, I have a very bad temper."

(A.J. Liebling)