In 1915, Thorpe Jr. began his professional football career after a season with the baseball Giants. The Canton Bulldogs were reformed (the team went on hiatus after a 1906 scandal), and they scheduled a game against the Massillon Tigers. These teams had their initial professional football beginnings back in 1902.

This was Thorpe's first experience with professional football. The game occurred midway between Massillon and Canton, Ohio; the towns are about eight miles apart. That afternoon, Thorpe met Knute Rockne for the first time. Rockne played end for Massillon, while Thorpe was a halfback for Canton.

Jim Thorpe undoubtedly played his best football with Canton in those first few years, surpassing his Carlisle performances. Jim surprised the sports world with his speed and skill. He played this challenging game until he was 41. He could hit an opponent with tremendous force, which became evident on this fateful day against Massillon.

Once, Thorpe faced a young, eager tackle trying to impress his teammates with his toughness, believing professional football was perfect for him. He was overly enthusiastic about tackling and wouldn't stop. So, the next time he went for a tackle, Thorpe says he stopped, intentionally dropped the ball, and the brash Massillon end picked it up. Then, bam! He didn't see it coming; the "Burley Indian" struck him, and he was knocked unconscious.

Thorpe told him not to do that again, but how could he respond? He was out cold.

That was the first encounter of football legends Jim Thorpe and Knute Rockne.