RABO DIRECT PRO 12: ULSTER v EDINBURGH
Ulster centre Luke Marshall will play in the Pro12 clash with Edinburgh after being released from Ireland duty.
Fellow centre Darren Cave has also been released by Ireland while Craig Gilroy, who starts at full-back, and lock Iain Henderson return after injury lay-offs.
Grayson Hart is ready to make his Edinburgh debut from the bench, as is lock Ben Toolis, while full-back Tom Brown returns to the visiting squad for the first time since injuring his ankle in pre-season.
The Ulster centre said that he had been consoled by Ireland coach Joe Schmidt immediately after the game and told to move on from the mistake.
However with Schmidt now opting to release Marshall back to Ulster duty this weekend there will be speculation that Gordon D'Arcy will resume his long-standing centre partnership with Brian O'Driscoll in Sunday's international.
In terms of the Ulster selection, Diack has described being named as captain as a "tremendous honour".
"It was a bit of a shock when Mark (Anscombe) called out the team and I was captain," said Diack.
"I am hugely excited to be leading out such a talented bunch of guys and hopefully we can get the win."
Callum Black, Rob Herring and John Afoa are named in an unchanged front row, with Lewis Stevenson and Henderson starting in the second row.
Sean Doyle, who was man of the match for the Ravens last week, is picked at openside and Nick Williams starts at number eight.
Ireland internationals Tom Court, Dan Tuohy and Roger Wilson are named on a strong bench.
Ulster lie fifth in the Pro12 standings and six points behind leaders Munster, while Edinburgh are back in ninth.
Ulster: C Gilroy, A Trimble, D Cave, L Marshall, M Allen, J McKinney, P Marshall, C Black, R Herring, J Afoa, L Stevenson, I Henderson, R Diack (capt), S Doyle, N Williams.
Replacements: N Annett, T Court, R Lutton, D Tuohy, R Wilson, I Porter, P Nelson, R Andrew.
Edinburgh: G Tonks, D Fife, J Dominguez, B Atiga, J Cuthbert, H Leonard, S Hidalgo-Clyne, W Blaauw, A Lutui, WP Nel, O Atkins, I van der Westhuizen, T Leonardi, R Grant (capt), C Du Preez.
Replacements: J Hilterbrand, R Hislop, G Cross, B Toolis, R Rennie, G Hart, S Beard, T Brown.