Jack Borotsik played two years of major junior hockey in Brandon with the Wheat Kings of the WCHL before playing at the University of Brandon for one season. He is honoured as a forward on the school's 1960's All-Star Decade Team along with his brother Ron. Despite a strong yet short collegiate career, NHL scouts rarely took notice of university hockey in the 1960s, and so Borotsik went undrafted. He had hoped to land a contract offer but none was forthcoming.
In 1970-71 he signed a contract with the IHL's Dayton Gems and quickly emerged as one of the team's most dominant offensive forces, scoring 53 points in 71 games. He followed that up with a 71-point season the next year.
Borotsik recorded his first pro hat trick while playing for the Denver Spurs of the WHA in a game against the Tulsa Oilers during the 1972-73 season. He had put in a strong offensive performance and came off the ice after scoring his second goal of the game. Coach Jean-Guy Talbot leaned over to Borotsik on the bench and said "are you tired?" to which the response was "no." Talbot put his speedy centre back out on the ice and he notched his third goal of the game with just 29 seconds to play, making the final score 6-2. The "are you tired" question was intended as a motivational ploy, which Borotsik answered to perfection.
Borotsik played just one game in the NHL with the St. Louis Blues in 1974-75, and although he failed to record a point, it was by far the highlight of his career. He continued to play hockey for another few years, retiring in 1978 after playing for his hometown Brandon Olympics of the CSHL.