Major League Soccer: Top five playoff contenders for 2018

Jim Reineking | USA TODAY

Show Caption Hide Caption David Beckham announces new MLS team in Miami David Beckham takes to stage to announce his new Major League Soccer franchise in Miami. Video provided by Reuters

A total of 20 different teams have qualified for the Major League Soccer playoffs in the previous three seasons.

In 2017, there were seven different playoff teams that did not make the postseason in 2016. In 2016, there were four teams that did not make the playoffs in 2015. Four teams have made the playoffs in each of the previous three seasons (Toronto FC, Seattle Sounders FC, New York Red Bulls and Sporting Kansas City).

While more postseason turnover is expected in 2018, here are five teams that are expected to make this season's playoff field:

Toronto FC

The reigning champions are coming off the most impressive season in league history. Powered by the triumvirate of Jozy Altidore, Michael Bradley and Sebastian Giovinco, TFC remains the team to beat this season. Aside from aspiring to become the first MLS team to win the CONCACAF Champions League, Toronto FC will attempt to be the fourth team in league history to repeat as MLS Cup champions (L.A. Galaxy, 2011-12; Houston Dynamo, 2006-07; D.C. United, 1996-97).

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Seattle Sounders FC

The Sounders have made the playoffs in each of their nine MLS seasons, the longest active postseason run in the league. That streak should hit 10, even with the season-ending injury to Jordan Morris. Seattle made it to MLS Cup for a second consecutive year despite injuries to Morris and Ozzie Alonso. Newcomers such as Will Bruin and Gustav Svensson were impactful replacements and helped the team win the Western Conference crown. That plug-in-play, next-man-up mentality is reminiscent of another routinely successful sports franchise that's on a run of nine consecutive playoff seasons, the New England Patriots.

Atlanta United FC

For as long as the Sounders had existed in MLS, they set the standard for attendance. Then, Atlanta United FC came along, setting new single-game and season-average attendance records. The fan fervor was a result of the team's tremendous on-field success in its first season. Under coach Gerardo "Tata" Martino, Atlanta United played an appealing, high-scoring brand of soccer. In 2017, Atlanta had 13 games in which it scored three or more goals. That included a 6-1 battering of Minnesota United on a snow-covered pitch in the second-ever game for either team, and a late-season 7-0 demolition of the New England Revolution. Atlanta added more firepower for 2018, acquiring Ezequiel Barco on an MLS-record transfer fee and signing U.S. national teamer Darlington Nagbe.

New York City FC

Under the direction of Arsenal and French legend Patrick Vieira, NYCFC has reached the Eastern Conference semifinals in each of the past two seasons. Despite the loss of Italian soccer icon Andrea Pirlo, NYCFC — alongside Atlanta United FC — figures to challenge Toronto FC for Eastern Conference supremacy. Jesus Medina, a 20-year-old midfielder from Paraguay, was acquired to fill the void left by Pirlo. This is considered an upgrade; Pirlo made just 14 starts during the 2017 season and appeared in only one playoff game. David Villa remains the nexus of this squad, and NYCFC's title hopes still ride on his ability to consistently light up the Yankee Stadium scoreboard.

New York Red Bulls

Second to Seattle's consecutive seasons of reaching the playoffs is the Red Bulls' eight-year run. For the second consecutive offseason, the Red Bulls traded away their team captain (Dax McCarty in 2017, Sacha Kljestan in 2018). Despite the on-field and off-field upheaval (such as getting rid of coach Mike Petke following a Supporters' Shield-winning 2015) through the years, this team manages to contend annually for playoff berths. With an attack anchored by Bradley Wright-Phillips and young American Tyler Adams running all over the field, third-year coach Jesse Marsch should have an exciting, conference title-contending team in 2018.

Follow USA TODAY Sports' Jim Reineking on Twitter @jimreineking.