“We will have to wait to find out the extent of his injury and the test result,” Bento said on Monday.
Mourinho told reporters on Sunday: “It’s muscular. Muscular is always not easy … He is a guy who normally recovers very, very well from any kind of injury.”
The national team selection could be further complicated by regulations in place for the coronavirus pandemic.
Clubs are usually obliged to release players called up for international duty but, according to rules introduced by Fifa in February, can refuse if players will face quarantine periods of more than five days.
However, with Son an elite athlete and returning from a country not on the British government’s ‘red-list,’ he would not be required to quarantine upon return to Spurs.
There has been criticism in South Korea over the decision to play the friendly in the midst of a global pandemic.
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In November, the national team visited Austria to play Mexico and Qatar and, during the training camp, four players tested positive for the virus. South Korean team officials are confident there’ll be no repeat of that this time.
“We conducted a thorough safety review and our medical team will be much better prepared than in November,” Bento said. “We don’t have much time to train before World Cup qualification and I am just trying to make the best of the situation I have.”
South Korea and Japan are preparing for the resumption of Asian qualifiers for the 2022 World Cup in June. The most recent games in qualifying were in November 2019.