Five best teams in Major League Soccer history

Toronto FC — behind goals by U.S. national team stalwart Jozy Altidore and Victor Vazquez — avenged a penalty-shootout loss to the Seattle Sounders in last year's title game to claim its first MLS Cup championship.

The MLS Cup victory capped the most impressive season in league history, with Toronto FC becoming the first Major League Soccer team to complete the domestic treble (domestic cup competition, Supporters' Shield and MLS Cup).

Are these accomplishments enough to make Toronto FC the best team in league history?

Here are MLS's top five teams. In order to be considered, a team must have prevailed in the league's most important game: MLS Cup.

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5. 1998 Chicago Fire

Coached by future U.S. national team manager Bob Bradley, the Fire became — and remain — the only expansion team in league history to win MLS Cup (only two expansion teams in the past 10 years — Seattle and Atlanta — have even reached the playoffs). The Fire also pulled off a domestic double by winning the U.S. Open Cup. This season kicked off a run of three MLS Cup appearances in six seasons for Chicago, who couldn't recapture that championship magic of its inaugural season.

4. 2007 Houston Dynamo 

Houston defeated the New England Revolution in consecutive MLS Cups (2006-07), and are one of three teams to win consecutive MLS Cups. The 2007 championship capped an impressive run for a group of players who won four MLS Cups in seven years (including two in San Jose before a relocation to Houston). 

3. 1999 D.C. United

This was D.C. United at its apex, winning the third MLS Cup title in the first four seasons of the league's existence. In order to claim that third championship trophy, D.C. United had to go through the Los Angeles Galaxy, who were also a league powerhouse that had the misfortune of being on the wrong end of two of those D.C. United MLS Cup wins. 

2. 2011 Los Angeles Galaxy

The Galaxy teams that won back-to-back MLS Cups in 2011-12 possessed arguably the most loaded rosters in league history. Coached by Bruce Arena, the Galaxy featured players such as Landon Donovan, David Beckham, Robbie Keane, Omar Gonzalez and Mike Magee. The Galaxy's 2011 season was more impressive, as it also collected the Supporters' Shield. In 2012, the Galaxy started slowly (they were 3-8-2 heading into June), finished fourth in the Western Conference, but peaked in time for another championship run.

1. 2017 Toronto FC

In beating the Seattle Sounders in an MLS Cup rematch, TFC pulled off something no MLS team had in the 21 years prior: winning the domestic treble (Canadian Championship, Supporters' Shield and MLS Cup). The collective accomplishments of this team make it the most impressive in league history. Toronto FC had the most points in a single season (69) in league history, the most wins in a season (20) that didn't have a shootout decide a winner (MLS broke ties with shootouts from 1996-99), the second-most goals for and the second-best goal differential in league history.

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