Calac recalled in Robert W. Wheeler's book, Jim Thorpe: World's Greatest Athlete, that the other players took an interest in him because of his large size.

Thorpe and Calac soon became friends and would later play professional football with the Canton Bulldogs and the Oorang Indians.

[3] After attending West Virginia Wesleyan, Pete returned to California for a visit to family and tribe and enlisted in the Army.

However, in an article by the Professional Football Researchers Association, Calac was reported to have suffered career threatening wounds during the war but was back at the top of his game by 1922.

[4] In 1916 with Calac and former Carlisle teammate Jim Thorpe starring, Canton went 9–0–1, won the Ohio League championship, and was acclaimed the pro football champion.

Then in 1919 Thorpe and Calac were joined in the backfield by future Hall of Famer Joe Guyon and won their third Ohio League Championship.

Calac and Guyon joined the backfield of the Union Quakers over the 1921 Thanksgiving weekend for the games against the Conshohocken Athletic Club and the pre-NFL version of the Frankford Yellow Jackets.

In the winter of 1921, Walter Lingo, an Airedale terrier breeder, brought Thorpe and Calac, to his plantation in LaRue, Ohio to hunt for possum.

As part of this big name spending spree, Calac was offered a contract to serve as the team's fullback.

The combination of Hughitt, Boynton, Eddie Kaw, and Calac gave Buffalo the most potent offensive backfield in the league.

In a 13–0 opening day victory over the Columbus Panhandles, managed by future NFL President Joe Carr, Calac was knocked out of the game with a broken nose.

Take a look at a backfield like Jim Thorpe, Joe Guyon, Pete Calac and Frank Mount Pleasant."