SA flank Jaco Kriel is to have a second operation on his injured shoulder that will probably sideline the Springbok loose forward for the next six months.
Kriel, who captained the Lions in the 2017 Super Rugby final, was injured playing for the Boks against Australia last September and immediately had surgery on his shoulder.
However, that operation was unsuccessful and he will have a second surgery on Thursday.
"Due to unforeseen circumstances the operation that Jaco Kriel underwent on his shoulder was unsuccessful and needs to be repeated on March8," the Lions said on Wednesday.
"He is expected to be sidelined for a further six months."
Kriel will now miss the start of the international season for the Boks, who play Wales in Washington on June 2, before hosting England for three Tests the same month.