Peter McKinnon was born in Scotland. He started his soccer career as a goalkeeper with the Portobello Renton Junior club in 1935. He was about to reach his best years as a goalkeeper when he joined the Armed Services in March 1940. While serving in the Army in World War II he became a prisoner of war.
After doing army service Peter joined Bo’ness United of the Edinburgh League in April 1946. Peter’s performances in goal for Loanhead Mayflower in the 1947-48 season dubbed him as one of the best goalkeepers in Scottish Junior football. Peter remained with Loanhead Mayflower until March 1953, when he sailed for Canada.
In Canada Peter joined Toronto Thistles. In 1956 he won the Ontario Cup with the Thistles and helped the club reach the Eastern finals of the Canadian Challenge Trophy.
Peter was the goalkeeper for the Polish White Eagles in the 1957 National Soccer League season.