South Korea sweat on Son as Uruguay await

South Koreans are anxiously awaiting news of whether captain Son Heung-min is available when they need him most, as the Asian giants start their World Cup campaign against a Uruguay side with a track record of deep runs in the tournament.

The Tottenham forward sustained multiple fractures around his left eye three weeks ago and has been training in Qatar wearing a black protective mask.

Son's unrelenting threat and firepower against an uncertain Uruguayan defence will be vital if South Korea are to pick up some crucial early points on Thursday (12am Friday AEDT) in a group which also includes Portugal and Ghana.

South Korea coach Paulo Bento has imposed a team gag order on discussing Son's state of World Cup readiness, hoping to keep Uruguay's strategists in the dark.

"We should check and analyse day by day, let him come," Bento said in the run-up to Qatar.

"We have time to make the right decisions and the best decisions for all of us."

Son is eager to play despite the possibility of further injuries from a premature return, last week saying he was "more than willing to bear those risks".

Uruguay are something of a dark horse at the tournament, with a squad that combines a trusted old guard of players aged 35 or above, with exciting young talent eager to make a mark in their first World Cup.

They include Liverpool's record signing Darwin Nunez, who is expected to be paired up front with the ageing Luis Suarez.

At 23, Nunez is 12 years younger than Suarez and fellow forward Edinson Cavani, who play in their fourth World Cup, as does captain and most-capped player Diego Godin.

Among 13 debutants will be Real Madrid's versatile Federico Valverde and Manchester United's Facundo Pellistri, who will link up with Tottenham's in-form Rodrigo Bentancur in a strong midfield.

Coach Diego Alonso sees the age gap as a boon and believes Uruguay - semi-finalists in 2010 - could win this World Cup, as they did in 1930 and 1950.

That could be a tall order, with observers noting frailties at the back that South Korea could exploit, particularly in the centre, while there is no word yet on whether Barcelona's Ronald Araujo is available after thigh surgery.

Uruguay have reached 14 World Cups and South Korea 11, but neither has a good record in their opening match.

The Asian side have lost or drawn in their last two World Cups, with Uruguay unable to win their openers in six of their last seven appearances.