Arturo Vidal felt Alexis Sanchez needed his goal for Chile against Japan after a "difficult" season with Manchester United.

Sanchez scored his first goal since January as the two-time defending Copa America champions beat Japan 4-0 in Sao Paulo on Monday.

The Manchester United attacker headed in a cross from Charles Aranguiz in the 82nd minute before setting up Eduardo Vargas a minute later.

Vidal said the goal was just what Sanchez, who netted twice in 27 games for United in 2018-19, needed.

"Alexis needed the goal. He had a difficult year and this gives him confidence," the midfielder said.

The late goals wrapped up Chile's win after Erick Pulgar's first-half header and Vargas' deflected strike in the 54th minute.

Vidal, whose team face Ecuador in Group C on Friday, urged Chile to continue improving.

"We must focus from now on that game," he said.

"We know that if we keep improving we can be a very dangerous team."