A heavily deflected effort from Kelvin Leerdam, a sumptuous strike from Victor Rodriguez, and a late Raul Ruidiaz breakaway goal put the home side out of sight before Jozy Altidore's consolation in the dying moments.
Though the result was conclusive, there are some lingering questions relating to the match and the futures of both clubs going into the next campaign.
When Leerdam's 57th-minute shot pinged past Quentin Westberg via a generous bounce off Justin Morrow's left leg - an own goal in every league in the world except MLS, it seems - it was against the run of play. Toronto FC were in the ascendency until that point and, despite Seattle's subsequent outburst, the end-of-match statistics indicate the visitors dictated proceedings throughout.
|Statistic||Seattle Sounders||Toronto FC|
|Shots on target||6||5|
But maybe TFC were sucked into the Sounders' gameplan.
Brian Schmetzer's players ceded control of the midfield while they focused on forging a low block that hushed their opponents. Alejandro Pozuelo desperately cropped up in deeper positions than would be expected of a false nine as he tried to influence the game, and Tsubasa Endoh and Nicolas Benezet were largely ineffectual before their respective withdrawals in the 62nd and 68th minutes.
Seattle was always dangerous on counterattack, too. Jordan Morris spearheaded a few upfield forays with powerful runs into the Reds' territory. As the resolute hosts tried to see out the result at 2-0, a lurking Ruidiaz corralled a long punt and shrugged off Chris Mavinga before confidently putting the result beyond doubt.
This was no smash-and-grab win for Seattle. Schmetzer and his staff masterminded this triumph.
Days after February's 4-0 CONCACAF Champions League loss to Panamanian minnows Club Atletico Independiente de la Chorrera, Greg Vanney seemed confused.
Toronto FC's head coach had repeatedly cited Manchester City as an influence on his team's approach during preseason, but he then namechecked another club that appeared the antithesis of the English champions.
"The way a team like Atletico Madrid defends - their commitment to defending, their commitment to getting numbers between the ball and the goal, and then how they step out - is something that we've also looked at," Vanney told theScore at the time. "(It's) something that we need to take on."
Although a large part of Toronto FC's postseason run was a credit to Vanney's in-game management, there was still little indication he'd settled on a distinct team identity by the time the final arrived.
TFC experimented with 10 separate formations during the regular season, according to Whoscored. When the "TAM wingers" - Benezet and Erickson Gallardo - arrived in July to allow Vanney to comfortably deploy a Manchester City-esque 4-3-3, it wasn't a comfortable fit for Pozuelo. And eventually, it included the hard-working yet limited Tsubasa Endoh rather than Gallardo.
TFC struggled for consistency in both approach and lineup until the playoffs; perhaps it was fitting they were undone by a side with the stellar organization and familiarity of Schmetzer's ranks.
The departure of Osvaldo Alonso before this campaign felt like the end of an era, but the continuity in the Sounders' lineup remains strong.
Five members of Seattle's starting XI - Stefan Frei, Roman Torres, Joevin Jones, Cristian Roldan, and Nicolas Lodeiro - were starting their third MLS Cup final. Two of the team's three goalscorers were included from the first whistle for the 2017 MLS Cup final defeat on TFC's home turf.
And why would Schmetzer be in a rush to change anything? Frei was assured between the sticks; Torres - perhaps surprisingly given the nod over Xavier Arreaga - bludgeoned a game-high 15 clearances; Jones' versatility enabled the halftime tweak that put Seattle in control; Roldan put in an all-action midfield display; Lodeiro, the Uruguayan playmaker, posted more key passes than anybody else (five).
Torres, 33, is the likeliest to depart in the offseason, but don't be surprised if Schmetzer begins the 2020 campaign with many of the players that have defined his miraculous tenure thus far.