NHL Playoff Sweeps Without Surrendering Lead

When a team wins the first four games of a playoff series they are said to have swept the series and their opponent. When the victor does so NEVER trailing in any of the four games, they have completed the rare feat of a PERFECT sweep.

Of the 666 best-of-seven NHL Stanley Cup playoff series played through 2017, 115 (17%) have resulted in a sweep.  Only 18 of those 666 series (2.7%), however, ended in a perfect sweep or annihilation.

The chart below describes every such perfect sweep (or annihilation, if you prefer), showing the playoff year, matchup and round of the rarity.

Year	Matchup	Round
1946	Montreal over Chicago	Semifinal
1952	Detroit over Montreal	Final
1954	Montreal over Boston	Semifinal
1960	Montreal over Chicago	Semifinal
	Montreal over Toronto	Final
1969	Boston over Toronto	Quarterfinal
	St. Louis over Philadelphia	Quarterfinal
1977	Montreal over St. Louis	Quarterfinal
1978	Montreal over Toronto	Semifinal
1979	New York* over Chicago	Quarterfinal
1987	Detroit over Chicago	Preliminary
1989	Pittsburgh over New York**	Preliminary
1992	Chicago over Detroit	Quarterfinal
1995	Detroit over San Jose	Quarterfinal
2000	Detroit over Los Angeles	Preliminary
2009	Detroit over Columbus	Preliminary
2013	Boston over Pittsburgh	Semifinal
2015	Chicago over Minnesota	Quarterfinal

*   New York Islanders
** New York Rangers

The Montreal Canadiens lead the league with six perfect sweeps and are the only team to do it twice in a single postseason. That happened in 1960 when Montreal annihilated both the Chicago Blackhawks and Toronto Maple Leafs en route to their fifth straight Stanley Cup championship. Chicago, on the other hand, owns the honor of being on the losing end of a perfect sweep four times, leading all teams in this category.

Breaking it down by round, the most annihilations have happened in the Quarterfinal (7), followed by the Semifinal (5), Preliminary (4) and Final (2).  The last team to be so swept in the Cup Final was the Toronto Maple Leafs 55 years ago, adding to their dreary postseason history.

Of the two sweeps thus far in the 2018 Stanley Cup Playoffs (San Jose over Anaheim, Vegas over Los Angeles), both victims managed to hold a goal lead at some point during a game of the series avoiding the distinction of making this historic list. 
Beware of the brooms. But avoid annihilation at all costs.

* See also NHL Stanley Cup Playoff Sweeps.