Lionel Messi makes MLS debut: How does the league work?

When Lionel Messi made his long-awaited Major League Soccer debut on Saturday, he achieved two familiar outcomes since joining Inter Miami: The team won, and the Argentinian superstar scored.

Prior to Messi’s arrival, Inter Miami were winless in their previous 10 games. But in a few short weeks, the Argentinian World Cup winner helped change the trajectory of the club.

With Messi on the pitch, Inter Miami have won their last nine matches, picking up their first major trophy along the way. He has scored 11 goals during that early stretch.

Saturday’s 2-0 win against the New York Red Bulls, however, was Miami’s first league fixture in more than a month and the first for Messi, who came off the bench to score.

Even with the Argentina captain on their roster, Inter Miami still will have a mountain to climb to keep their MLS hopes alive. The team currently sit second from last in the Eastern Conference with 21 points from 23 games.

Messi had propelled Inter Miami to victory in the Leagues Cup, a cup-style tournament that pits MLS teams against Mexico’s Liga MX sides. He also helped the team reach the final of the US Open Cup, a competition akin to the FA Cup in England, featuring dozens of teams from different domestic leagues.

Now Inter Miami will try to make a push for a playoff spot to keep their hopes of winning the MLS Cup alive. Messi is set to have his full debut in the league on Wednesday against Nashville SC.

Al Jazeera looks at the North American league and how it operates.

How many teams are in the league?

The MLS has 29 clubs, including three Canadian teams.

What are conferences?

Given the vastness of the United States and Canada, the teams are broken into two conferences to reduce travel. The Eastern Conference features 15 teams, and 14 are in the Western Conference.

Inter Miami are in the Eastern Conference. Title holders Los Angeles FC are in the Western Conference.

During the regular season, teams play all the sides in their conference at least twice and a handful of teams from the opposing conference for a total of 34 matches.

What are playoffs?

At the end of the regular season, the league breaks into a knock-out style tournament, known in North American sports as playoffs.

The team with the most points from either conference after regular league play concludes win the Supporters’ Shield, but the MLS Cup – largely seen as the more prestigious prize – is won at the end of the playoffs.

How do playoffs work?

The MLS playoff system has evolved over the years, and in this season, there is a new format.

The top seven teams from each conference automatically make it to the playoffs. The eighth and ninth clubs will play a single knockout game to book the “wild card” final qualifying spot.

The playoffs are played by conference. Conference playoff winners then meet for the MLS Cup final at the end of the season.

In the quarterfinals of each conference, teams must win a best-of-three series of matches to advance. There are no aggregate scores and no ties at that stage. The team that finished higher in the league host the first match. In the case of a draw, the game goes directly to penalty kicks – no extra time.

The conference semifinals, finals and MLS Cup final return to the single-game format with possible extra time before penalties. These games will be hosted by the higher seeded club.

How far are Inter Miami from a playoff spot?

Messi’s Inter Miami are 11 points behind ninth-placed Chicago Fire in the Eastern Conference, but they have played two fewer games. (They are 33 points behind conference leaders FC Cincinnati.)

They have 11 games left to salvage a playoff position.

Does the MLS have promotion and relegation?

No. Much like other top North American sports leagues, the MLS does not have promotion or relegation. Commercially viable teams are always guaranteed a spot in the league.

While there are other professional and semi-professional football leagues in the US and Canada, they do not lead to promotion to the MLS.

How do new teams join the league?

The MLS kicked off in 1996 with just 10 teams. It has been expanding ever since. Inter Miami took the field for the first time in 2020.

The latest team to join the MLS were St Louis City SC this season. The California city of San Diego is also set to have its own club in the league, which will be the MLS’s 30th team, starting in 2025.

To join the league, new clubs have to pay a “buy-in” fee, which has been growing over the years. The new San Diego club owners agreed to a $500m expansion fee with the MLS this year.

The MLS requires new clubs to have owners with robust finances willing to invest in the league. The team must also be based in a market with a viable fan base, and it has to have “comprehensive” stadium plans.

Does the MLS pause for international breaks?

Not always. Unlike most leagues around the world, the MLS does not suspend play during international breaks, leading teams to sometimes play without key starters who are called up to their national teams.

The league will stop for the international windows in October and November, but it will play on – albeit with a lighter schedule – during the international games in September.

Inter Miami coach Tata Martino recently said that he expects Messi to miss at least three games this season when he joins Argentina for 2026 World Cup qualifiers.

What do MLS officials say about the league’s format?

There was a time when penalty shootouts in the MLS took place with players dribbling the ball from the halfway line to beat an onrushing goalkeeper, so the league has always played by its own rules.

Daniel Courtemanche, MLS executive vice president for communications, told Al Jazeera last month that the league is “young” at 28 seasons, which has allowed it to “be innovative and do things differently”.

“We are the North American dialect of the world’s game,” he said.