Bulls' loose forward Dewald Potgieter has suffered another injury setback, this time a hamstring injury, and has been ruled out of Super Rugby for another four to six weeks.

Potgieter returned to his first Super Rugby action of the season at the weekend, having recovered from a severed tendon in his arm.

The Bulls' player injured his hamstring 10 minutes into the match against the Lions at Ellis Park on Saturday.

"Dewald suffered a grade two tear and will be out of action for between four and six weeks," team doctor Org Strauss confirmed.

Werner Kruger (shoulder), Wynand Olivier (hamstring), Flip van der Merwe (groin), Akona Ndungane (knee) and Dean Greyling (ribs) will all miss training on Monday and Tuesday.

Greyling will undergo a fitness test later in the week after a scan revealed no serious injury to his ribs.

Deon Stegmann will also complete his rehabilitation on a hamstring injury this week and will be fit to travel with the Bulls when they tour Australia and New Zealand later in the month.

Willie Wepener (Ramsay Hunt syndrome) is also recovering slowly, with no date yet set for his return.