Tomáš Plekanec
This one still seems odd, a career Montreal Canadiens forward, Tomáš Plekanec was a third round selection by the team in 2001. He would play 14 years, 981 games and have a trio of 60-point seasons wearing the Canadiens jersey, however, with his team well out of the playoffs and the Maple Leafs continuing to make strides in year two of the Auston Matthews era he was traded to Ontario.
Montreal landed a couple of prospects that never amounted to anything, as well as a second round pick that is still playing in Europe. Plekanec would be underwhelming on the Maple Leafs roster collecting just two assists in 17 games during the regular season, but lifted his play during the playoffs. Plekanec collected a pair of goals and four points in a seven game series loss to the Boston Bruins before he would return to Montreal in free agency.
His time in Toronto was very short, but the memories of Canadiens fans seeing the turtle neck under the Maple Leafs jersey can't sit well with them.
Jacques Plante
With no disrespect to the Carey Price, the three most famous Montreal Canadiens goalies has to be Jacques Plante, Patrick Roy and Ken Dryden. Plante is most famous for being the best goalie of his generation, introducing the goalie mask and being a legendary Canadiens goalie.
During Plante's years in the NHL the Toronto and Montreal rivalry was at it's peak. The Shawinigan Falls native would play 11 seasons in the blue, white and red where he would win six Vezina trophies and as many Stanley Cups. However, as he aged, the franchise management decided to trade him to the New York Rangers where he would play a couple of seasons before retiring.
After a couple seasons away from the NHL, Plante came back and joined the St. Louis Blues between the pipes; and at the age of 42 he did what everyone Canadiens fan hated and joined the Toronto Maple Leafs. Some may think, he could not have been that good anymore being in his early 40s, however, he was just as dominant and even finished fifth in Hart Trophy voting in 1971 when he posted a 1.89 GAA and .944 save percentage.
Plante would finish his 106 game Maple Leafs career with a 48-38-15 record recording a 2.46 GAA and .925 save percentage, which puts him 21st all-time wins and tied for the franchise lead in save percentage.