In a game that had already seen two goals and a red card, it was a goalline clearance in the 76th minute that spoke as the clearest statement of Inter Miami’s intent for the remainder of the 2024 MLS season.

Hosting fellow Eastern Conference contenders FC Cincinnati at Chase Stadium, Miami raced into an early two-goal lead thanks to a Luis Suárez brace. Twice Tata Martino’s side pounced on careless turnovers by the visitors inside the first six minutes, and twice the veteran Uruguayan striker finished ruthlessly inside the penalty area.

But then as half-time drew near, 20-year-old central defender Tomás Avilés showed his inexperience, being sent off for a second yellow card after a reckless challenge near midfield that was worthy of a straight red.

Miami were already without the injured Lionel Messi for the eighth consecutive MLS game. Up against the reigning Supports’ Shield champions and, after the addition of MVP candidate Luciano Acosta at the mid-season break, 10-man Inter might have crumbled. After all, they were facing one of the few attacking units in MLS that can equal their creativity and firepower. But the action of another defender in pink epitomised their commitment to clinging on.

Related: Lionel Messi pledges future to Miami and admits there is ‘not a lot of time left’

Paraguayan center-back David Martínez was making his MLS debut after arriving on loan from River Plate in July. Despite being such a recent recruit, the 26-year-old showed he was reading from the same playbook as his new colleagues – who’d pressed doggedly to unsettle the Cincy players in possession – when he raced back to clear a goal-bound effort from inside the six-yard box.

Martínez’s intervention helped preserve a clean sheet and three points for Miami, clinching a playoff berth in the process. But they achieved much more beyond that, too.

Through a combination of international duty and an ankle injury sustained in Argentina’s Copa América final victory over Colombia, Miami have been without Messi since 2 June. Of the eight MLS games Messi has missed in that time, Inter have now won seven, finding a way to win without their most talented and most important player.

The only game Inter lost over that stretch was an embarrassing 6-1 defeat to Cincinnati last month. Suarez and Jordi Alba were both absent for that one, too, while Sergio Busquets, who was playing out of position at center-back, was sent off.

With Suárez and Alba restored to the lineup for the return fixture – and with Busquets, although still deployed in defense, making it through the full 90 minutes – Miami exacted revenge, opening up a six-point lead over the East’s second-placed side.

The win cemented Inter’s status as Supporters Shield frontrunners and kept alive the prospect of a record regular-season points hall. Currently on 56 points and with eight games to play, the current MLS high mark of 73 points – set by the New England Revolution in 2021 – is in reach. If they maintain their current league-best average of 2.15 points a game, Martino’s men will equal that tally.

And it’s an ominous prospect for the rest of the league that Messi, according to Martino, is nearing a return.

“Leo, like I said the other day, I can’t tell you exactly what time, but he’s already on the field,” the Inter coach said after the Cincinnati win. “He is working with his physical therapist, he’s out of the medical ward, he is training with a ball. He has to get back in shape or recover most of his fitness that any player loses when they are out for five or six weeks, and to feel confident that his injury is behind him. But it is something that I believe is not very far from happening.”

That’s not to say Miami will have a straightforward path to an MLS Cup title, however. The Eastern Conference is stacked, with Cincinnati and the Columbus Crew capable of upsetting the current East leaders.

Columbus, the reigning MLS Cup winners, have won five of their last seven MLS games and, during the mid-season break, were crowned Leagues Cup champion. In Cucho Hernández, who has 15 goals and eight assists from 22 all-competitions appearances this year, the Crew boast arguably US soccer’s most in-form player right now, while Wilfried Nancy is on a very short list of the league’s most innovative coaches.

Out West, Conference leaders Los Angeles Galaxy have just added former Germany and Borussia Dortmund icon Marco Reus, who scored and assisted on his MLS debut this past weekend. And LAFC, last year’s MLS Cup runners-up, have added World Cup-winning target man Olivier Giroud to a fearsome attack that already included last season’s Golden Boot winner Denis Bouanga, who has 22 goals and 14 assists from 33 games this term.

Related: With Luis Suárez, Messi may not even be the best player on his own team

“Of course, our goals are set super high and our standards are set super high,” said Inter Miami goalkeeper Drake Callender, who was excellent against Cincinnati. “We want to win – we want to win the Eastern Conference, we want to win MLS Cup.”

And winger Diego Gómez agreed that the Herons’ ambitions stretch far beyond simply making the postseason. “We achieved our first objective, which is to make it to the playoffs,” he said. “We have to keep going, we still have to keep training, we have to keep improving.”

The players’ words post-game only re-emphasised what the team’s performance had already made clear: after a disappointing Concacaf Champions Cup campaign and with their Leagues Cup defence falling short in the last-16 stage, it’s MLS Cup or bust for Inter Miami.