John Ziegler Jr., the NHL president who oversaw the merger with the World Hockey Association and was eventually ousted following labor unrest and a players’ strike in 1992, has died.

He was 84.

The NHL confirmed Ziegler’s death on its website, although the cause was not immediately known. He was living in Florida.

Ziegler was the NHL’s fourth president, succeeding Clarence Campbell in 1977 and serving 15 years. He was the first American to run the league and was inducted into the Hockey Hall of Fame in 1987.

Two years after he became president, the NHL merged with the WHA. It added four teams from the upstart league — the Edmonton Oilers, Winnipeg Jets, Quebec Nordiques and Hartford Whalers.