Luke Marshall, the Ulster centre, has been released for selection after a 15-month absence due to a knee injury.
Marshall, 31 years old, was forced from Scarlets in November 2020 due to his latest long-term injury.
He was part of Ulster’s rugby championship squad that traveled to matches against the Stormers and Bulls on Saturday.
Sam Carter is currently unable to work due to a Covid-19 infection.
After sustaining a hamstring injury four weeks ago, Prop Tom O’Toole is back in training.
Marshall, who has won 144 caps for Ulster since his debut in the Ulster, has had his career hampered by injuries in recent years.
He was injured in his hip in July 2020 and was out of action for four more months. His return to action in November that year was cut short by Scarlets’ knee injury.
Dan McFarland, Ulster coach, feels a boost from the return of his Ireland contingent. Second row Iain Henderson is also back, but Robert Baloucoune was not able to travel to South Africa.
Ulster are one point behind Leinster, the URC leaders, in Pretoria and Cape Town respectively.
Stormers and Bulls games: Ulster squad
Forwards:Bradley Roberts, Andy Warwick and Bradley Roberts.
Backs:Ben Moxham. Billy Burns. Craig Gilroy. Dave Shanahan. Ethan McIlroy. James Hume. John Cooney. Luke Marshall. Nathan Doak. Rob Lyttle. Stewart Moore. Stuart McCloskey.