18 May, 11:09
IRFU Chief Executive Philip Browne has issued a statement following confirmation of Ronan O'Gara's decision to retire from playing professional rugby.
Tom Court, Ed O'Donoghue, Stephen Ferris and Paul Steinmetz are all promoted from the replacements bench, while Ulster captain Rory Best and young back rower David Pollock both return from injury for this crucial clash.
Darren Cave and Cillian Willis are given the nod ahead of Rob Dewey and Paul Marshall, who have both been dropped from the matchday squad.
Explaining his selection decisions, Matt Williams said: "The changes I have made are all based on performance, apart from Kieron Dawson. Kieron was exceptional last week and has been our best player lately.
"He is on the bench only because we are giving him a rest from the starting line-up this week.
"It's great to have Paul Steinmetz back to full fitness. He had an operation during the summer and we are so pleased to finally get him back on the pitch.
"I thought Paul played well against the Ospreys and provided quality leadership on the pitch.
"Darren Cave is also back in the team. He is very strong defensively. We tried a different centre partnership against the Ospreys and it didn't work, so we are going to see if Cave and Steinmetz will work tomorrow night.
"Timoci (Nagusa) needs a break. He has been starting in every game and I want to give him a rest on the bench."
The Ulster boss knows what to expect against Edinburgh and has been keeping a close eye on them recently.
"Edinburgh are a very good side, Andy Robinson is a world class coach and their defence has improved enormously under his direction," he explained.
"They had a great win over the Scarlets a few weeks ago and played some high quality rugby against the Dragons last weekend. They know our form has been poor of late, and will be coming over here looking for a win."
It is no secret that Ulster have not had the best start to their Magners League campaign, but following on from some stern words with his squad on Monday, Williams is realistic about what the players need to do.
"The squad are all really looking forward to the game tomorrow night. We want to make amends for what happened in Swansea. We all know our performance was below standard and we're looking forward to putting things right.
"The players really need the supporters over the next few months. They are going through a hard time and need the Ulster supporters to get behind them and will them to a win.
"I would love to see that Ulster spirit in the support throughout the province."
Tickets for Friday's game are still on sale and can be purchased online at the Ulster Rugby website, over the counter at Ravenhill (Monday to Friday from 9pm to 5pm), over the telephone (028 9049 3222, Option 2) or through any of the ticket outlets throughout the province.
ULSTER (v Edinburgh): Bryn Cunningham; Clinton Schifcofske, Darren Cave, Paul Steinmetz, Andrew Trimble; Niall O'Connor, Cillian Willis; Tom Court, Rory Best (capt), BJ Botha, Ed O'Donoghue, Ryan Caldwell, Stephen Ferris, David Pollock, Robbie Diack.
Replacements: Nigel Brady, Justin Fitzpatrick, Carlo Del Fava, Kieron Dawson/Matt McCullough, Isaac Boss, Ian Humphreys, Timoci Nagusa.