First, the club moved from the Western to the Eastern Conference of the National Hockey League (NHL).
Toronto qualified for the Stanley Cup playoffs and made it to the Eastern Conference Finals before losing to the Buffalo Sabres.
The 1998–99 season was a tremendous improvement for the Maple Leafs over the 1997–98 season and the team got plenty of help from its new members, including Bryan Berard, Sylvain Cote, Curtis Joseph, Alexander Karpovtsev (who led the NHL in plus-minus with +39, but was not eligible for the NHL Plus-Minus Award because he played just 58 games), Yanic Perreault and Steve Thomas (who finished second on the team in points, with 73).
Toronto set a club record for most regular season wins (45) and earned 97 points to finish second in the Northeast Division and fourth in the Eastern Conference.
With the series victory, the Sabres advanced to the Stanley Cup Finals for the first time in 24 years.