[1] These were the last Stanley Cup playoffs conducted under a format that paired teams in each round without regard to division or conference standing.
The Toronto Maple Leafs earned 71 points during the regular season to finish sixteenth overall in the league.
The Blues and Penguins traded goals in the third period, giving Pittsburgh a 6–4 victory that tied the series at a game apiece.
The Montreal Canadiens entered the playoffs as the Wales Conference and Norris Division champions, earning 103 points.
The Edmonton Oilers earned 74 points during the regular season and finished fourteenth overall, losing the tiebreaker with the New York Rangers in wins (30 to 29).
The Oilers gained a 6–3 victory in game one, in large part due to Wayne Gretzky's five-assist night.
The Rangers won game one in large part due to the impressive goaltending performance of Steve Baker, as he turned away 31 of the Kings' 32 shots.
Ranger forwards Ron Duguay and Ulf Nilsson each scored a goal in every game of this series.
The Buffalo Sabres entered the playoffs as the Adams Division champions, earning 99 points, losing the tiebreaker with the Los Angeles Kings in wins (43 to 39).
This was the second playoff meeting between these two teams, and was a rematch of last year's Preliminary Round, where Buffalo defeated Vancouver in four games.
The Sabres swept Vancouver in three games, eliminating the Canucks in the preliminary round for the second consecutive season.
Buffalo forced game one to overtime as Andre Savard scored the tying goal with just 8 seconds left in the third period.
Rookie centre Alan Haworth scored the game-winning goal for Buffalo five minutes into overtime.
The Quebec Nordiques earned 78 points during the regular season and finished eleventh overall, losing the tiebreaker with the Chicago Black Hawks in wins (31 to 30).
This series also marked the first appearance of a team representing Quebec City in the Stanley Cup playoffs in 68 years.
Quebec completed the comeback 37 seconds into overtime as Dale Hunter scored the game-winning goal.
Ken Linseman's three points in the third period of Game 5 helped ensure a Philadelphia series-clinching win, 5–2.
This series also marked the first appearance of a team representing Calgary in the Stanley Cup playoffs in 56 years.
However the Black Hawks came up short in double overtime as Willi Plett scored the series-clinching goal for the Flames at 15:17.
The North Stars earned 87 points during the regular season and finished ninth overall, losing the tiebreaker with the Bruins in wins (37 to 35).
Minnesota won game one in overtime due to Steve Payne's hat trick goal at 3:34.
The North Stars scored four times in the first period of game three and they did not relinquish the lead, eliminating the Bruins with a 6–3 win.
Denis Potvin's hat trick and five point night in game two led the Islanders to a 6–3 victory.
[5] Anders Hedberg's go ahead goal in third period of Game two was just the second successful penalty shot in Stanley Cup playoff history.
[7] Steve Christoff and Dino Ciccarelli each scored twice for the North Stars in game two as Minnesota took a 2–0 series lead with a 5–2 victory.
Buffalo goaltender Don Edwards made 43 saves in a losing effort in game three as the Sabres lost by a score of 6–4.
Don Beaupre made 36 saves for Minnesota in game five as they advanced to the Stanley Cup Semifinals for the second consecutive season.
Willi Plett gave Calgary the lead early in the third period of game three and Pat Riggin made 47 saves in the Flames 2–1 win.
Forward Ken Linseman's second goal in game six for Philadelphia held up as the game-winner as the Flyers avoided elimination with a 3–2 triumph.
With the win Calgary became the first relocated team in league history to advance to the third round of the playoffs in their inaugural season in their new location (this feat was later surpassed by the Colorado Avalanche in 1996).