The Tottenham Hotspur striker could miss 'a number of weeks'.
Son suffered the injury early on in Spurs' 3-2 win at Aston Villa on Sunday,
But he powered through to score two of his side's goals - including a stoppage-time winner.
Tottenham released a statement on Tuesday, in which they revealed the issue and confirmed that Son will undergo surgery later this week.
The South Korean, who has scored in each of Spurs' last five matches, joins another striker, Harry Kane, on the sidelines.
And he is expected to miss 'a number of weeks'.
It is a diagnosis which prompted Roberts to tweet the following message upon hearing the news.
Just hearing the news re sonny , come on sonny bandage it up and get out on the pitch and score some more goals get it fixed in the summer we need you— Graham Roberts (@GrahamRoberts4) February 18, 2020
Tottenham host RB Leipzig in the last 16 of the Champions League on Wednesday, with one of Dele Alli, Lucas Moura, Steven Bergwijn or Troy Parrott in line to lead Jose Mourinho's attack.
Neither Alli, Lucas or Bergwijn are orthodox centre-forwards, while Parrott has played just twice for the Spurs first team.
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