Ulster centre Luke Marshall has been made available for selection after 15 months out with a knee injury.
Marshall, 31, was forced off against Scarlets in November 2020 in his latest long-term injury set back.
He has travelled with Ulster's squad for their United Rugby Championship matches away to the Stormers on Saturday and the Bulls the following week.
However, Sam Carter is unavailable following a recent Covid-19 infection.
Prop Tom O'Toole has returned to training following a hamstring injury sustained four weeks ago.
Marshall, who has won 144 caps since making his Ulster debut, has seen his career beset by injuries in recent seasons.
A hip injury sustained in July 2020 kept him out of action for four months until his return to action that November, which in turn was cut short by the knee injury sustained against Scarlets.
Ulster head coach Dan McFarland is boosted by the return of his Ireland contingent, including second row Iain Henderson, but Robert Baloucoune has not travelled to South Africa.
Ulster sit one point behind leaders Leinster in the URC ahead of their double-header in Cape Town and Pretoria respectively.
Ulster squad for Stormers and Bulls games
Forwards: Alan O'Connor, Andy Warwick, Bradley Roberts, Callum Reid, Duane Vermeulen, Eric O'Sullivan, Gareth Milasinovich, Greg Jones, Iain Henderson, Jordi Murphy, Kieran Treadwell, Marcus Rea, Marty Moore, Matty Rea, Mick Kearney, Nick Timoney, Rob Herring, Tom O'Toole, Tom Stewart.
Backs: Ben Moxham, Billy Burns, Craig Gilroy, Dave Shanahan, Ethan McIlroy, Ian Madigan, James Hume, John Cooney, Luke Marshall, Michael Lowry, Nathan Doak, Rob Lyttle, Stewart Moore, Stuart McCloskey.