The Italian side's victory at Cardiff Arms Park - their first PRO12 success, was a blow to Phil Davies' side but with their senior players returning, the Blues travel across the Irish Sea with an almost full strength side available.
British & Irish Lions skipper Sam Warburton returns to Davies' starting line-up after a remarkable recovery from a hamstring injury suffered on the summer tour to Australia. Fellow tourists Leigh Halfpenny and Alex Cuthbert also feature from the off.
"It's great to have Sam back in full training. It's the senior players who have to help the junior players along," said Rees.
"We've all had big games in our careers, we've had some lows and some highs as well which are part and parcel of the sport we play in.
"We've got two massive games now before we go into the Heineken Cup. It's important we start performing and if we do that, the result will look after itself."
Warburton's return is one of five changes for the trip to Dublin. Harry Robinson returns on the left wing while Wales scrum half Lloyd Williams is recalled to partner Rhys Patchell. Rees features alongside Sam Hobbs in the front row, Hobbs making his first start of the season at loosehead.
Looking back on the performance against Zebre, Rees added: "We're frustrated and disappointed. We've come back in this week and had a good look at ourselves.
"To lose at home isn't good - we spoke in pre-season about making it a fortress. We're all professional rugby players and we know it's not acceptable what happened on Friday night.
"We've got an opportunity now to go to the RDS and it's a big challenge.
"It's a tough place to go and play but at the end of the day, these are the games you want to be involved in. You want to test yourself against the best and that's what we'll do on Friday night."
Scrum half Williams, said: "The first 20 minutes in Dublin will be massive and whoever gets on top then will win the game.
"It's going to be a tough test in Dublin but it will be a great opportunity.
"Who's to know what will happen on Friday but we're putting the building blocks in place to get the right result. It's a great boost to have Sam back - he's the Lions captain and a legend now."
Leinster include their British & Irish Lions with Irish internationals Brian O'Driscoll, Cian Healey and Jamie Heaslip all starting.