Dave Semenko played junior hockey for the Brandon Wheat Kings. He was originally selected 25th overall in 1977 by the Minnesota North Stars of the National Hockey League and the Houston Aeros of the World Hockey Association. The Aeros traded Semenko to the Oilers just before their 1977–78 season. He spent his first two professional years as a member of the Oilers in the WHA before the NHL–WHA merger. He scored the final goal in WHA history in Game 6 of the 1979 Avco Cup finals, which the Oilers lost to the Winnipeg Jets. When the Oilers then joined the NHL, Semenko’s rights were still held by the North Stars. The Oilers traded their second and third round picks in the 1979 NHL Entry Draft to acquire his rights from the North Stars who then drafted future hall-of-famer Neal Broten. The trade also gave the Oilers a third round pick, which was used to select future Oilers superstar Mark Messier. An acknowledged enforcer, he was Wayne Gretzky’s on-ice bodyguard early in Gretzky’s career in Edmonton, beginning in the WHA in 1978, and ending when Semenko was traded to Hartford in 1986. Dave Semenko is considered one of the toughest players ever in the NHL. The protection offered by Semenko allowed Edmonton’s stars — Gretzky, Jari Kurri, Mark Messier, and Paul Coffey — more freedom on the ice, contributing to the Oilers’ Stanley Cup triumphs in 1984 and 1985. After Gretzky won a car for being chosen as the MVP of the 1983 NHL All-Star game, he gifted the car to Semenko to show his appreciation for his on-ice work.

He fought boxing legend Muhammad Ali in an exhibition on June 12, 1983. The match was officially a draw after going three rounds, but the Associated Press reported that Ali was not seriously trying and was just toying with Dave Semenko. After brief stops with the Hartford Whalers and Toronto Maple Leafs, he retired following the 1987–88 season. He finished his 575-game NHL career with 65 goals, 153 points, and 1175 penalty minutes. Semenko also recorded 70 fights over his career. Semenko died on June 29, 2017, 13 days before his 60th birthday and shortly after being diagnosed with liver and pancreatic cancer.