River Plate seal 3-1 win over Platense in Argentina

River Plate secured a 3-1 home win over Platense in their opening match of Argentina's Clausura championship on Sunday after the visitors were reduced to 10 men in the second half when midfielder Marcos Portillo was sent off.

River got off to the perfect start in the Group B match with a goal in the seventh minute when forward Facundo Colidio cut inside and fired home a stunning right-footed effort.

Platense equalised through forward Ronaldo Martinez's header in the 24th minute but striker Maximiliano Salas netted 15 minutes later to restore River's lead, flicking in a low cross from Colidio to score on his debut for the club.

Platense's task became more difficult when Portillo was sent off in the 75th minute for elbowing Gonzalo Montiel, and Miguel Borja added a third for River in added time to wrap up a comfortable win at the Estadio Monumental in Buenos Aires.

River were playing for the first time since the Club World Cup, where they finished third in their group and failed to reach the knockout stage.

Coach Marcelo Gallardo's side were also looking to restore some confidence after being knocked out of the Apertura tournament quarter-finals by eventual champions Platense in May.

"I'm happy. We played a great game," forward Salas told TNT Sports. "It's nice to start with a win, it gives us confidence to keep working hard. With a lot of humility and hard work, we're going to improve.

"Sometimes you can play badly, well or averagely, but the most important thing is to give it your all. On the pitch, you have to give it your all, and whether you score or not is secondary."

River next visit Instituto ACC on Saturday, while Platense host Velez Sarsfield.