Toronto FC has won its first MLS Cup championship, and completed one of the most impressive seasons in league history.

TFC defeated the Seattle Sounders, 2-0, in MLS Cup at BMO Field on Saturday.

In doing so, Toronto earned a unique place in Major League Soccer history. Toronto is the first team in league history to win the domestic treble. The MLS Cup win capped a season in which Toronto also won the Canadian Championship and the Supporters' Shield.

Jozy Altidore finally broke through against Sounders goalkeeper Stefan Frei in the 67th minute to put Toronto FC up 1-0. Victor Vazquez added an insurance goal in the final minute of stoppage time to secure TFC's win.

Toronto FC dominated possession for much of the game, and spent the first half pelting the Sounders' goal with shots, but goalkeeper Stefan Frei — the hero of Seattle's win in last year's MLS Cup in Toronto — was up to the challenge.

Seattle was attempting to become just the fourth Major League Soccer team to win consecutive league championships, last accomplished by the Los Angeles Galaxy in 2011-12.

Lineups

Seattle Sounders — Stefan Frei; Kelvin Leerdam, Roman Torres, Chad Marshall, Joevin Jones (Nouhou Tolo, 91st); Cristian Roldan, Gustav Svensson, Nicolas Lodeiro, Clint Dempsey, Victor Rodriguez (Jordan Morris, 71st); Will Bruin.

Toronto FC — Alexander Bono; Steven Beitashour, Drew Moor, Chris Mavinga, Justin Morrow; Michael Bradley, Marco Delgado (Benoit Cheyrou, 93rd), Jonathan Osorio (Armando Cooper, 85th), Victor Vazquez; Sebastian Giovinco, Jozy Altidore (Nick Hagglund, 86th).