Lionel Messi scored a screamer and won his first trophy in North American soccer as Inter Miami beat Nashville on penalties (10-9) after their final ended 1-1 in 90 minutes.

The Argentine World Cup winner had put Miami ahead in the 24th minute with a wonder strike into the top corner but Fafa Picault levelled for Nashville in the second half.

After Messi hit the post and Leonardo Campana missed a last second chance to win the game in regulation for Miami, the game went to a shoot-out which ended in a duel between the two keepers and Elliot Panicco's shot being saved by Miami's Drake Callender.

Messi and his team-mates rushed to celebrate with the American goalkeeper, who had made some key saves late in the game to keep his team alive.

Miami, in their third season of existence, were rock bottom of Major League Soccer when Messi joined them a month ago but Messi, along with Spanish pair Sergio Busquets and Jordi Alba, has utterly transformed the team leading them on a seven game unbeaten run to the League Cup title.

Co-owner David Beckham, who created the club, said he was stunned by the way the former Barcelona trio had been able to bring about change so quickly.

"It is like a movie, you watch these players play and it is, emotionally, everything about their play is beautiful,” he said.

Seven-times Ballon d'Or winner Messi has now scored 10 goals in seven games in the pink shirt of his new club and on Wednesday has the chance to reach another final when his team take on Cincinnati in the semi-final of the US Open Cup.

This was not the dominant, entertaining Miami that in the past month has lit up the tournament, featuring MLS and Mexican Liga MX clubs, but the win was sweet nonetheless.

"I am very happy to win our first title in just one month, the club's first. The team is growing by leaps and bounds and we are very happy," said midfielder Busquets.

- Leaps and bounds -

"We have infected the team with our spirit, our work, our character and experience. We are making a solid team ... And then we have Leo, who makes a difference because he's the best in the world."

Nashville set out with the clear intention to limit the impact of Busquets and by extension Messi and they were effective in forcing Miami to play a slower type of possession football, deeper in their own half.

Gary Smith's side sent an early warning that they could trouble Miami at set-pieces with Walker Zimmerman's header from a Lukas MacNaughton corner forcing Callender into a low save.

Miami were probing, with Messi dropping deeper and looking for gaps in the home defense.

But with Walker Zimmerman marshalling the back line well chances were hard to come by until Robert Taylor spun and turned and fired a fierce drive which Nashville keeper Elliot Panicco did well to keep out.

Three minutes later, Miami had the lead --  and the source of their breakthrough was no surprise.

Taylor's attempted pass inside was blocked and the ball fell to Messi who zipped past Zimmerman, opening enough space to his left to unleash an unstoppable drive from over 25 yards out which flew into the top corner past the helpless Panicco.

Miami looked in total control, playing with confidence bordering on swagger, but it was a different story after the interval.

From a corner Picault won a header at the back post which ricocheted in off the foot of Benjamin Cremaschi and Callender.

Suddenly Nashville had the belief and their German forward Hany Mukhtar came alive, testing Miami with his speedy runs and Callender with a blast from the right.

Messi went close to another Hollywood ending with a 71st minute shot from just outside the box which shaved the outside of the post.

But in the final seconds, his Ecuadorian team-mate Campana should have won the game for Miami, when he rounded Panicco but from a tight angle could only hit the post with the goal at his mercy.

Then came penalties and with all 10 outfield players having shot, with one miss for each side, it came down to the keepers and Callender kept his cool with his shot before denying Panicco and launching the celebrations.

While the players sprayed champagne in the locker-room, Argentine coach Gerardo 'Tata' Martino was in reflective mood.

"The most important thing we had to do is put together a team while we were playing a seven-game tournament, and that's very difficult to do," he said.

"We now have greater clarity about what the future may hold for us after winning this title in 30 days".