Chile have been pleased with how Ben Brereton is shaping up for their World Cup double-header after his hypobaric chamber build-up work to adapt to the games at high altitude.

Brereton met up with the national team over the weekend for games with Argentina on January 28 and Bolivia on February 1.

Chile have switched their training camp and home match with Argentina to Calama due to the increased altitude level ahead of the away game at Bolivia.

While that won’t pose as many issues for the majority of the Chile squad, Brereton has been acclimatising in the UK by using a hypobaric chamber to gear up for games in Calama (2,260 metres above sea level) and La Paz in Bolivia (3,600 metres).

Brereton is pencilled in to start the crucial qualifier with Argentina as part of a front three with Alexis Sanchez and Eduardo Vargas.

And national team boss Martin Lasarte has been pleased with what he has seen from Brereton in training.

“I see Ben Brereton well in his movements and sensations. There are adaptation guidelines that we are trying and he has told us that he is very well,” he said.

Lasarte also credited Brereton’s learning of Spanish which he said ‘speaks well of him’.

The qualifying double-header represents a big challenge for Chile to keep their hopes of qualifying for Qatar 2022 alive.

With four games remaining, Chile are a point behind fourth-placed Colombia who currently occupy the final qualification place and also a point off Peru in fifth which will be good enough to earn a play-off slot.

Chile face Brazil and Uruguay during the March break, likely meaning that La Roja will need at least two wins two stand any chance of qualifying.

Knowing the importance of the games and the potential problems associated with playing at altitude, Brereton has been acclimatising to the changing oxygen levels through the use of a hyperbaric chamber for the last two months.

Chilean sports journalist Juan Cristóbal Guarello explained: “What Chile has compared to Argentina is that altitude is not an issue, for the Chilean player it is not a matter of having to play at altitude because they has been playing there for four decades.

“Brereton is not one of those, but he prepared for two months. What Ben did is that of a professional player.

“He really worked two months to be able to play this double date, it is something totally worth imitating and highlighting.”

Brereton has become a key man for Chile since pledging his allegiance to the country of his mother’s birth last summer.

He has three goals in nine appearances but coronavirus restrictions and scheduling have brought difficulties.

The 22-year-old didn’t meet up with the Chile squad for their September fixtures due to the country being placed on the UK Government’s red list.

The Chile federation and Rovers were at odds as a result and the club were threatened with FIFA action only for an agreement to be reached that saw Brereton feature in all three matches in October, scoring in wins over Paraguay and Venezuela.

Hen then started the November win over Paraguay only to miss the Ecuador defeat due to suspension.

Rovers then released Brereton for the two matches this week, his absence spanning two Championship fixtures, the win over Middlesbrough the first time he’s not been involved in a matchday squad this season.

He will also miss the trip to Luton Town this weekend before travelling back ahead of the game with Swansea City on Saturday, February 5.