From 1988 through to 1991 Potvin played with the Chicoutimi Saguenéens, a Quebec Major Junior Hockey League (QMJHL) team. In the 1990–1991 season Potvin was awarded the Guy Lafleur Trophy as Playoff MVP.
Potvin was drafted in the 2nd round, 31st overall by the Toronto Maple Leafs in the 1990 NHL entry draft. In the 1991–1992 season, Potvin played 35 games for the St. John’s Maple Leafs, compiling a 2.93 GAA. For his efforts, Potvin was awarded the Dudley “Red” Garrett Memorial Award (rookie of the year), the Baz Bastien Memorial Trophy as the top goaltender in the AHL and selected to the AHL First All-Star Team. During that season, Potvin was called up to the NHL and saw brief action in 4 games, compiling a 2.28 GAA and a .933 save percentage.
It wasn’t until the 1992–1993 season that Potvin became a regular in the NHL. That season he played 48 games, compiling a 2.50 GAA (1st in the NHL) and a solid .910 save %. The rapid acceleration of his development led the coaching staff to establish him as their #1 goaltender, and prompted the trade of Grant Fuhr to the Buffalo Sabres. That season, Potvin also backstopped the Maple Leafs to the Stanley Cup conference finals, only to lose to the Los Angeles Kingsin a grueling seven game series. His efforts did not go in vain, however. His dynamic performance made him a finalist for the Calder Trophy.
In the 1993–94 season, Potvin silenced any doubts of a sophomore jinx. He posted 34 wins and a solid 2.89 GAA, including tying Kirk McLean’s then NHL record for most wins in October with nine. He was also voted to his first NHL All-Star Game. In the 1993–94 playoffs, Potvin recorded 3 shutouts in the first-round series against the Chicago Blackhawks, all by a 1–0 margin, including the final NHL game ever played at the illustrious Chicago Stadium. He also became the first Maple Leafs goaltender to stop a penalty shot in a Stanley CupPlayoff game, when he stopped Chicago’s Patrick Poulin. Potvin again brought his team to the conference finals, this time losing to the Vancouver Canucks in five games.
In the 1995–1996 season, Potvin was selected to his 2nd NHL All-Star Game. However, the Toronto Maple Leafs exited in the first round of the playoffs.
In the 1996–1997 season, with the aging of the defense corps in front of him, Potvin and the Maple Leafs would miss the playoffs. He would set an NHL record for most shots faced in a season, 2,438, later broken by Roberto Luongo during his stint with the Florida Panthers.
In the 1998–1999 season, Toronto signed free agent Curtis Joseph, leaving Potvin expendable. He would play in only 5 games due to a knee injury, before he and 6th round pick (Fedor Fedorov) were traded to the New York Islanders for defenceman Bryan Berard and a 6th round pick. Despite the new surroundings, Potvin was unable to reclaim the success he had earlier in his career.
In the 1999–2000 season, Potvin, a 2nd round, and 3rd round draft pick were traded to the Vancouver Canucks for Kevin Weekes, Dave Scatchard and Bill Muckalt. Potvin struggled with the Canucks and in the 2000–2001 season he was dealt to the Los Angeles Kings for future considerations. Immediately, Potvin made an impact in a Kings uniform. He led the Kings to the 7th seed, recording 13 wins and 5 losses, and a remarkable 1.96 GAA and a .919 save %. Potvin led the Kings to a first-round upset of the Detroit Red Wings, and pushed the eventual Stanley Cup Champions, the Colorado Avalanche, to a 7th game, recording 2 shutouts in that series.
Potvin again led the Kings to the 2002 playoffs, where they pushed the Colorado Avalanche to seven games in the 1st round.
In September 2003, Potvin was signed to a 1-year contract by the Boston Bruins. He backed-up Calder Trophy Winner Andrew Raycroft during the 2003–04 season. Coincidentally, Raycroft broke Potvin’s record for consecutive games played by a Maple Leafs goalie during the 2006–07 season. Potvin has not played for an NHL team since the 2003–04 season.
Early in the 2005–06 season, the Atlanta Thrashers were in talks with Potvin in hopes of signing him after starting goaltender Kari Lehtonen and backup goaltender Mike Dunham went down with injuries. However, Potvin did not have equipment that conformed to the new NHL standards, nor did he wish to accept the two-way contract that was being offered to him, so the Thrashers instead decided to sign Steve Shields.
- 1995–1996 NHL All-Star Team
- 1993–1994 NHL All-Star Team
- 1992–1993 NHL All-Rookie Team
- 1991–1992 AHL Dudley “Red” Garret Memorial Trophy
- 1991–1992 AHL Baz Bastien Memorial Trophy
- 1990–1991 CHL Goaltender of the Year
- 1990–1991 QMJHL Jacques Plante Trophy
- 1990–1991 QMJHL Guy Lafleur Trophy
- 1990–1991 QMJHL Hap Emms Trophy