The New York Red Bulls let slip a lead to lose 2-1 to Sporting Kansas City on the opening weekend of the new Major League Soccer (MLS) season.
Caden Clark had put the Red Bulls up with a spectacular goal early in the second half but last season's Western Conference top spot finishers hit back.
Gadi Kinda netted a 59th minute penalty with Hungarian forward Daniel Salloi putting KC ahead barely 60 seconds later with a simple close-range finish.
New York City were also opening day losers, blowing a 1-0 lead to go down 2-1 at D.C. United.
City, who reached last season's play-offs, went ahead on the quarter hour from Valentin Castellanos.
But United responded by taking the lead before the interval with a sensational long-range drive from Brendan Hines-Ike and another from Russell Canouse, coming from a perfectly executed corner routine.
10-man Revolution hit back, Pato debut
Last season's semi-finalists New England Revolution fought back from two goals down to claim a thrilling 2-2 draw away to Chicago Fire.
Revolution, who were reduced to 10 men in second-half stoppage time after a DeJuan Jones red card, trailed 2-0 after 11 minutes following goals from Robert Beric and Luka Stojanovic.
Polish attacker Adam Buksa and Gustavo Gou netted in the following 15 minutes to level the match.
New England debutant Edward Kizza should have scored the winner when he struck the crossbar with an 87th minute header.
Victor Wanyama was among the goals as Montreal eased past Toronto 4-2 in their Canadian clash, while former Brazil international Alexandre Pato debuted for 2020 quarter-finalists Orlando City who had a scoreless draw with Atlanta United.
However, Pato limped off in the 80th minute with an apparent knee issue which will have Orlando sweating on scans.
Los Angeles FC started the new season with a solid 2-0 victory at home over newcomers Austin with goals from Corey Baird and Jose Cifuentes.
Nashville fought back from a two-goal deficit to draw 2-2 with Cincinnati thanks to Randall Leal's 64th minute long-range curler, while Dallas and Colorado also played out a 0-0 draw.
LAFC coach Michael Bradley admitted he "might have jumped the gun" when he accidentally subbed off star Mexican attacker Carlos Vela in the 22nd minute after he waved in his direction. In hindsight, Vela was calling for treatment from a trainer after picking up a knock.
Teenager's special strike
The Red Bulls went ahead when 17-year-old midfielder Clark fired in a superb volley out of mid-air. The teenager appears a star in the making.
Montreal 4-2 Toronto FC
Orlando City 0-0 Atlanta United
Los Angeles FC 2-0 Austin
Sporting KC 2-1 New York Red Bulls
FC Dallas 0-0 Colorado Rapids
DC United 2-1 New York City FC
Chicago Fire 2-2 New England Revolution
Nashville 2-2 Cincinnati
Galaxy in Florida
There's three games on Sunday including a glamour fixture between David Beckham's Inter Miami against his former club Los Angeles Galaxy.