Cape Town - Lions flank Vincent Tshituka will undergo surgery to his ankle on Wednesday after suffering a grade three sprain in Friday's 29-17 loss to the Waratahs.
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The 21-year-old had been in impressive form this Super Rugby season and had even caught the eye of Springbok management, but he now faces an extended spell on the sidelines.
Ruan Vermaak was named as Tshituka's replacement for the remainder of the tour and joined up with the squad in Melbourne on Sunday.
The Johannesburg based franchise will continue their tour with matches against the Rebels (Melbourne, March 7), Blues (Auckland, March 14) and Highlanders (Dunedin, March 21).
Friday's defeat was the Lions' third in four matches and leaves them in a lowly 11th place on the overall standings and fourth in the SA Conference.