Ulster's Darren Cave will return for the province against Oyonnax (1pm kick-off) after six weeks out this afternoon but Les Kiss's starting line-up is without three key men who took on Saracens last time out.
Ireland's new captain Rory Best is on the bench after suffering from a tight back during the week with Rob Herring taking his place as both starting hooker and team captain.
The returning Cave takes the place of Stuart McCloskey, called into Joe Schmidt's Six Nations squad for the first time on Wednesday, as the young centre is rested having featured in all of Ulster's games this season. There is also a change at scrum-half where an ill Ruan Pienaar is replaced by Paul Marshall as Paddy Jackson's half-back partner.
With the Springbok absent, David Shanahan is promoted to the bench.
Nick Williams has overcome the concussion he sustained in the reverse fixture and is back at number 8 with Roger Wilson dropping to the bench.
"It's great to have Darren and Nick back in the team," said Kiss.
"We welcomed Jared (Payne) back last week and that was pleasing for us too. With Rory on the bench it's another opportunity for Rob to show what a great player and what a great leader he is.
"Ruan has been struggling with illness all week so he is unavailable, but we know that Paul will come in and do a fantastic job for us."
With Chris Henry again absent with a shoulder injury, Sean Reidy continues at openside with Robbie Diack in the number six jersey.
Alan O'Connor and Franco van der Merwe continue in the engine room with Clive Ross providing cover for both lock and back-row. Up front, Herring will have Kyle McCall as his loosehead while, with Wiehahn Herbst out with a toe problem, it is Ricky Lutton filling the tighthead role.
Alongside Best on the bench, Callum Black and Bronson Ross provide the front-row cover.
The back-three is unchanged from last week's loss at Allianz Park, meaning Andrew Trimble and Craig Gilroy occupy the wing berths and Jared Payne continues at full-back.
The Kiwi-born Irish international played his first game since Ireland's World Cup win over Romania last time out and, with the Six Nations panel assembling after these European games, it is interesting to see him once again in the 15 jersey having played all his Test rugby at outside centre.
Cave occupies that position today, having played more inside centre in recent months, while Luke Marshall, who conversely has featured at 13 frequently of late but was previously considered a 12, has moved back inside.
Rory Scholes covers the outside backs while Ian Humphreys, a try-scorer last week, is on hand to replace Jackson.
With little to play for and a domestic relegation battle to concern themselves with, Oyonnax have made 14 changes from last week's victory.
The top table debutants earned their first ever win at this level at home to Toulouse last week but have a daunting slate of Top 14 fixtures - they face Racing 92, Toulon and Clermont in their next three games. Lock Geoffrey Fabbri is the only player retained from the win over Toulouse last Saturday but there are a few familiar faces in the shape of former Ulster favourite Pedrie Wannenburg and one-time Northampton Saint Soane Tonga'uiha.
Still, Kiss is aware of the threat posed by the outfit from the Rhone-Alps region.
"They are a good team and they will provide a big challenge for us," he said.
"We need to stay focused on our game, make our tackles, start the match with the right attitude and play with discipline, because they can hurt you if you give the ball away easily.
"They showed that last week against Toulouse and against us a fortnight ago."