Inter Miami forward Lionel Messi (10) and Atlanta United defender Derrick Williams (3) go after the ball during the first half of an MLS playoff opening round soccer match in Fort Lauderdale, Fla. (AP )

FORT LAUDERDALE, Fla., Nov 10, (AP): Lionel Messi walked off the field and into the tunnel leading to the Inter Miami locker room a few seconds after the final whistle blew, hardly any emotion on his face.

He didn't want to see the celebration.

Atlanta United ousted Messi and Major League Soccer's biggest-spending team earlier than anyone imagined from the MLS Cup playoffs. Jamal Thiaré scored twice, Bartosz Slisz's header in the 76th minute was the winner, and Atlanta United stunned Inter Miami 3-2 on Saturday night to win their best-of-three first-round playoff series in three games.

"There's some fairy dust in our locker room, man,” Atlanta United goalkeeper Brad Guzan said after stopping seven shots, some of them in spectacular fashion, and giving Slisz a big hug in response to his goal. "I couldn't be more proud of our guys.”

Two free kicks by Messi in the final minutes hit the wall of Atlanta defenders, and time eventually ran out on soccer's most decorated player and his team. Messi’s header - yes, header - in the 65th minute tied the match at 2-2, but the hosts never reclaimed the lead. Atlanta took the lead with an Inter Miami player down and the hosts lobbying for play to be halted, but the whistle never came and Slisz became one of many heroes for the winners.

"It’s everybody. It’s a joint effort,” Atlanta United interim coach Rob Valentino said. "We talked about it before the game, we talked about it all year long that it’s not going to be just one player. It’s a collective effort and that’s what happened tonight.

It was the fifth win-or-else victory for Atlanta United this season - starting with two must-win matches to keep hope alive at the end of the regular season against the New York Red Bulls and Orlando City, then a wild-card match at Montreal, Game 2 of this series at home and then Saturday’s stunner.

And the East is suddenly wide open.

Ninth-seeded Atlanta United will play No. 4 Orlando City in the Eastern Conference semifinal, while sixth-seeded New York City FC will face the seventh-seeded New York Red Bulls in the other East semifinal.

No. 2 Columbus was already gone. No. 3 Cincinnati was ousted on Saturday. And then came the biggest surprise of all - No. 1 Inter Miami’s season is over.