On February 12, 2003, Mike Leclerc scored just 10 seconds into the overtime period to give the Mighty Ducks a 4-3 home win over the Calgary Flames. It would prove to be the fastest overtime goal scored during the 2002-03 NHL regular season.
In what was a very large upset, the seventh-seed Mighty Ducks took a first-round series from the number-two seed and defending Stanley Cup Champions Detroit. The Mighty Ducks swept the Red Wings in four games to get revenge from 1997 and 1999 where the Mighty Ducks were swept by the Red Wings. In game one of the series, when the game went to overtime, the sellout crowd at Joe Louis Arena thought the Wings had won the game thanks to a Luc Robitaille shot at 9:21. Some of the Detroit players had even left for the dressing room. However, after going to the video review, it was concluded that Robitaille's shot ricocheted off the crossbar and the post, and the players were brought back to resume the game. Later, at 3:18 into the third overtime period, Paul Kariya scored the goal that would clinch a 2-1 win for Anaheim and a one-game lead in the series. Anaheim goalie Jean-Sebastien Giguere faced 64 shots in game one. In game two, Anaheim came back from a 2-1 Deficit by scoring two goals in the third period.
The Mighty Ducks won game three, at the Arrowhead Pond of Anaheim, 2–1 to push the Red Wings to the brink of elimination. The Mighty Ducks then won game four, a 3–2 overtime victory with Steve Rucchin delivering the knockout goal 6:53 into overtime. The Red Wings became only the second defending Stanley Cup champions to be swept the following year in a four-game opening series.
The series opened at American Airlines Center in Dallas, where the heavily favored Stars and underdog Ducks engaged in an epic battle that took over 140 minutes and four overtimes to decide before Anaheim's Petr Sykora scored the game-winner 47 seconds into the fifth overtime, winning the game for the Ducks, 4–3. Dallas goalie Marty Turco saw 54 shots while Anaheim's goalie, Jean-Sebastien Giguere, saw 63. Game 2 saw another game tied after 60 minutes, but this time, Anaheim needed only 1:44 to win the game in the first overtime, 3–2, on a goal by Mike Leclerc. Dallas, much like Detroit in its first-round series against the Ducks, faced a 2–0 deficit headed to Anaheim.
Game three at Arrowhead Pond of Anaheim was a must-win for the Stars, and they came through, winning the game, 2–1, getting two clutch goals from Jere Lehtinen. But the Ducks refused to let the Stars back in the series, winning Game four, 1–0, behind a 28-save shutout from Giguere. Not wanting to be eliminated in front of their home fans, a motivated Dallas team captured game five, 4–1. Unfortunately for the Stars, their bid to take the series to a game seven was denied when they were edged in game six, 4–3.
In game one, Petr Sykora scored at 8:06 into double-overtime in a 1–0 Mighty Ducks victory. It was the Mighty Ducks' second shutout of the playoffs. Jean-Sebastien Giguere turned in a stellar performance in net for Anaheim, stopping all 39 shots he faced. For game two, the Wild played Dwayne Roloson instead of Manny Fernandez in net. As in game one, it was another shutout for Giguere as the Mighty Ducks won the game 2–0. Both goals were short-handed, and Giguere stopped all 24 shots he faced, making him 63-for-63 in the series. In game three, Giguere continued his goal-tending excellence, stopping all 35 shots he faced in a 4–0 Mighty Ducks victory that pushed the Wild to the brink of elimination. Giguere had now stopped the first 98 shots he saw in the series. In game four, The Mighty Ducks won the game 2-1. Both goals came from Adam Oates, and the Mighty Ducks headed to their first Stanley Cup Final. The only good news for the Wild was that they avoided a fourth consecutive shutout, as Andrew Brunette scored the first Minnesota goal of the series. Still, Giguere was 122-for-123 in the series, a robust .992 save percentage.