Born in Tulsa, Oklahoma, he was a standout athlete at Arvin High School in California, and attended Bakersfield College and Cal Poly-San Luis Obispo.

He batted left-handed, threw right-handed, and was listed as 5 feet 9 inches (1.75 m) tall and 160 pounds (73 kg).

Jim Kennedy was originally signed by the New York Yankees in 1966 as a free agent, and was acquired by the Cardinals in the 1969 Rule 5 draft.

He spent most of the 1970 season in the city of his birth as a member of the Triple-A Tulsa Oilers, with his major-league trial occurring over four weeks spanning June 14 to July 9.

In the field, he started three games at shortstop and three at second, playing in 65 total innings and committing four errors in 43 chances (.907).