Carlos Queiroz's team became the first side into the knock-out rounds after following up Saturday's 2-0 win over Argentina with another victory over the Asian champions.

It was a deserved success but one that had looked likely to elude the 2001 champions as they toiled against a Qatar side that defended stoically and held on grimly for more than 85 minutes.

Qatar, who will host the next World Cup in 2022, may now need to beat Lionel Messi's Argentina in their final Group B match if they are to reach the last eight.

Vargas, who plays for Mexico club Tigres UANL, netted twice in the second half as defending champions Chile gradually overpowered a skillful but limited Japan, who are playing in the South American showpiece as one of two invited teams from Asia.

An Oscar Cardozo penalty and a stunning Derlis Gonzalez strike gave the South Americans a 2-0 lead in Rio de Janeiro but goals from Almoez Ali and Khoukhi in the final quarter snatched a share of the Group B spoils for the tournament debutants.

Based in the coastal town of Porta Belo for the last two weeks, Qatar have been in intense training for their debut in the world's oldest football tournament.

Qatar face Paraguay at the Maracana Stadium followed by Colombia on Thursday and gianst Argentina three days later. Argentina suffered a shock 2-0 loss to Colombia in their opening tie on Saturday.

Earlier in the day, Spanish giants Real announced the 18-year-old was joining the record 13-time European champions from FC Tokyo, to play for their B team next season.

"Being called the Japanese Messi is an honour and makes me proud, but I'm still not at his level and I prefer to concentrate on my abilities and strengths," said Kubo from Japan's Copa America base in Sao Paulo.

"I'm really looking forward to playing in the Copa America, it's one of the highest level tournaments in the world," the head coach told reporters in Sao Paulo.

"How can we show our strength and which way we play, that's what we want to find out in this tournament," the head coach of the AFC Asian Cup UAE 2019 runners-up added.

"We have decided to invite ... to participate in our competitions the current Asian confederation champions and the previous ones," said Alejandro Dominguez, the president of South American football's governing body.

The announcement came the day before the 2019 competition kicks off in Sao Paulo with hosts Brazil taking on Bolivia.

Qatar, the 2022 World Cup hosts, are participating in the Copa America as guests for the first time this year and line up in Group B alongside 14-time former winners Argentina, Colombia and Paraguay.