Lionel Messi's first trip to the MLS playoffs ended in shock disappointment but the World Cup winner has injected new life into Inter Miami and the North American top-flight, even as he finishes his first full season without the league title.

Messi's team had the best regular season in MLS history with a record 74 points but they could not keep up the momentum and were stunned by Atlanta United in the playoffs on Saturday.

It was bad news for those hoping to cash in on the world's most famous player reaching the finale, including Apple TV, who signed a blockbuster streaming deal with the league in 2022, and for broadcaster Fox, who will also air the Dec. 7 match.

But the 37-year-old has more than proven his worth for the league and his team, experts say, at a vitally important time for the sport in North America, where the World Cup will be staged in 2026.

"Messi has been the type of boost that MLS has needed. The issue for MLS has been attracting stars at the end of their career," said Andrew Zimbalist, a professor at Smith College and co-author of National Pastime: How Americans Play Baseball and the Rest of the World Plays Football.

"The special thing about Messi is that he is one of the top five soccer players of all time and even though he is now 37, he still can play, or at least have spurts of truly dominant soccer."

Messi expects Miami to be his final club, lending an air of urgency for fans who hope to catch a glimpse of one of the sport's all-time greats before his contract is set to expire at the end of next year.

Despite Saturday's setback, Messi and his Miami team mates will still compete in next year's expanded 32-team Club World Cup, which will be held in the United States.

The club co-owned by David Beckham were awarded a spot reserved for the host nation after they won the MLS Supporters Shield, which is given to the MLS side with the best regular game season.

The league announced last month an attendance record of more than 11 million fans across the regular season and Inter Miami told ESPN that they had nearly doubled their revenue since Messi signed in July last year.

Apple said that Messi's playoff debut was its most-streamed sporting event ever, while 72,610 fans packed into Arrowhead Stadium, the home of the NFL's Kansas City Chiefs, when Miami came to town to play Sporting Kansas City in April.

It was the fourth-largest standalone crowd in the league's history, MLS said.

"Messi carries with him a different vibe than past superstars who made many fans feel as if they were embarking on a U.S. farewell tour of sorts," said David M. Carter, principal of the Sports Business Group and an adjunct professor for sports business at USC.

"Messi helped demonstrate to the world that MLS remains serious about improving its global credibility and competitiveness."