Bulls openside flanker Deon Stegmann is in a race to be fit for his team's clash with the Cheetahs in Pretoria on Saturday.
Stegmann, who missed the Bulls' 21-20 defeat to the Rebels in Melbourne last weekend due to bruised ribs, will be given until Thursday to prove his fitness.
Meanwhile, midfielder Jan Serfontein has not recovered sufficiently from a knee strain and will miss the match against the Cheetahs.
Serfontein returned home from Australia two weeks ago due to the MCL strain and will not be risked on Saturday, Bulls team doctor Org Strauss confirmed.
JJ Engelbrecht (elbow), Burger Odendaal (hamstring), Jacques du Plessis (back) and Jesse Kriel (quad) have overcome niggling injuries and are back in training.