Cape Town - Springbok lock Eben Etzebeth may not be fully fit for the four home Tests against England in June.
The news comes after Stormers coach Robbie Fleck confirmed that the 26-year-old will not make a return to Super Rugby until July.
Speaking in Hong Kong, where the Stormers face the Sunwolves on Saturday, Fleck revealed that Etzebeth is only 85 percent fit.
"Eben hasn't even been passed fit medically yet," Fleck said on Thursday, as quoted by Citizen.
"To be honest, we'll only consider him after the international break. Realistically, we'll look at him for the game against the Jaguares.
"Whether he's involved with the national side before that is not my decision. That's up to Rassie Erasmus but we've been in contact with the Boks throughout Eben's injury. He's desperate to play again naturally but we want to make the best decision for the player," said Fleck.
Erasmus is also facing the prospect of having to do without star Lions hooker Malcolm Marx, Bulls lock Lord de Jager, incumbent skipper Warren Whiteley and flyhalf Pat Lambie.
The Boks open their season with a clash against Wales in Washington DC on June 2, before flying back home for the England series.
The first Test between the Springboks and England is scheduled for Ellis Park in Johannesburg on June 9, followed by Tests in Bloemfontein (Free State Stadium, June 16) and Cape Town (Newlands, June 23).
The Bok squad for the Tests will be named on Saturday, May 26.