RIO DE JANEIRO (Interstat) — A first-half strike from Kevin Serna was the difference as Fluminense opened its Carioca Série A campaign with a narrow 1-0 victory over Mirassol FC on Thursday at a rain-soaked Estadio Jornalista Mário Filho.

The match, the season opener for both clubs in the prestigious Rio de Janeiro state championship, was a tightly contested affair that failed to live up to its projected offensive output. Interstat’s game simulator had projected a 2-1 final score, but Fluminense’s single goal proved sufficient against a determined but ultimately outmatched Mirassol side.

Serna’s decisive moment came in the 31st minute, breaking a deadlock in a match that had been marked more by physical, stop-start play than fluid attacking football. The goal provided the home side with a lead they would not relinquish, despite a spirited effort from the visiting squad from São Paulo state.

The game’s physical nature was established early, with Mirassol’s Daniel Borges receiving a yellow card in just the third minute. The caution set the tone for a chippy first half that saw five additional players booked before the final whistle. Fluminense’s Luciano Acosta was shown a yellow in the 45th minute, just before halftime.

The second half continued in a similar vein, with four more yellow cards distributed by the officiating crew. The most concentrated period of dissent occurred in the 63rd and 64th minutes, when Mirassol’s Martinelli and Fluminense’s Renê were booked in quick succession. Mirassol’s Lucas Ramon joined them in the referee’s book in the 71st minute, and Fluminense’s Keno was cautioned in the first minute of second-half stoppage time.

Despite the victory, Fluminense was unable to capitalize on several opportunities to extend its lead, with the Mirassol defense holding firm under pressure for much of the match. The result defied the pre-match probabilities from Interstat’s ELO system, which gave Fluminense a 54.40 percent chance of victory, a forecast that proved correct, if slightly conservative regarding the final margin.

The win gives Fluminense an initial boost in the Carioca Série A standings, beginning its quest for the state title with a positive result at its iconic home stadium, commonly known as Maracanã. For Mirassol, the narrow loss, while disappointing, provides a foundation to build upon as the season progresses. Both teams now hold identical 0-0 records in the competition following the opener.

The match was the first of the season for both clubs across all competitions, setting their overall records at 0-0. The focus for both sides now shifts to their next fixtures in the Carioca Série A, where Fluminense will look to build momentum and Mirassol will seek its first positive result of the young campaign.