Tottenham forward Son Heung-min will be out for "a number of weeks" after fracturing his right arm, the Premier League club said on Tuesday.
The South Korea international suffered the blow during Sunday’s 3-2 win at Aston Villa, in which he scored two goals - including a stoppage-time winner.
Spurs revealed that Son will undergo surgery this week, which is a major setback as they prepare for Wednesday’s Champions League last-16 clash with RB Leipzig.
Son will also be absent for a crunch spell of Premier League fixtures, including a London derby with Chelsea on Saturday, as Tottenham bid to secure a Champions League spot.
News of the injury comes as a crushing blow to Spurs boss Jose Mourinho, who has been relying on Son to lead to provide firepower in the continuing absence of Harry Kane.
England captain Kane is battling to return before the end of the season after undergoing surgery on a torn hamstring injury suffered at Southampton on New Year’s Day.
Tottenham revealed in a statement: "Following surgery, our medical staff shall be reviewing management options for Son's rehabilitation with the player expected to be sidelined for a number of weeks."
Mourinho has few options remaining in attack, having not brought in a striker during the January transfer window.
Lucas Moura looks the likeliest player to play in a more advanced role, as Tottenham look to fill the gap left by Son, who has scored 16 goals for the club this season.
Tottenham also have Troy Parrott in their ranks, although the 18-year-old Republic of Ireland international has been used sparingly by Mourinho so far.
Mourinho may also look to the likes of Steven Bergwijn and Dele Alli to move forward.
Fifth-placed Spurs face Chelsea at Stamford Bridge after a first leg at home to Leipzig before a trip to Wolves as the battle for Champions League spots hots up.
They also face Manchester United and Sheffield United next month following the second leg at Leipzig on March 10.