‘The two of them bring a lot of power in particular’ – Cullen hails return of Porter and Kelleher

Cullen's men will take a five-point advantage into the game and having Porter and Kelleher back in situ will significantly enhance Leinster's chances of making it into the last eight of Europe.

Porter and Kelleher have been sidelined since respective knocks picked up during the Six Nations, and Cullen believes both players can make a big difference against Connacht.

Jordan Larmour was also available for selection following a hip issue, but Cullen opted to stick with Ciaran Frawley on the bench.

"It's huge, all the lads trained towards the end of last week, to bring Andrew and Ronan back in, that front-row has worked together quite a bit and it's a great combination to have,” Cullen said.

"Andrew, when he moved from tighthead to loosehead at the start of the season, he's a remarkable character and was going incredibly well until the injury to his ankle.

"Ronan has been training a bit longer because he's been able to do more, the two of them bring a lot of power in particular.

"Jordan was a little unlucky, he could come back into the team next week but it's great to have that power, it's much needed."

The third change to the Leinster team sees Jamison Gibson-Park getting the nod ahead of Luke McGrath, who started last week's first leg win at the Sportsground.

"In terms of Johnny (Sexton) and Jamison, they played together a lot during the Six Nations," Cullen explained.

"We'll see how the guys go, for us having that level of half-backs off the bench is hugely important to us as well and you can see how we've mixed and matched those guys over the course of a few seasons.

"We're blessed with the quality of those guys.”

Over 30,000 tickets have been sold so far for tomorrow's clash and Cullen is hoping his side deliver a big performance to seal their passage into the quarter-finals.

"The obvious thing is the start - start the game well. Connacht had us under the pump when they scored the try at the start of the game,” he said.

"There were some parts of the game when we were strong, in the scrum in particular, it's just trying to go after areas like that to establish dominance.

"It's going to be a great contest again, both teams want to have a strong attacking intent and one of Connacht's strengths is their phase attack and playing flat to the line, just defensively we have to be a bit sounder.

"It would be nice to get a good start to give us some control.

"We have to make sure our players have that emotional control, it's hugely important, the occasion is very important but we have to get to the pitch of the game and make sure we're in the right headspace, and make sure we're not over-aroused, I think that's the right phrase.

"For us it's a new game, a one-off, it's just a knock-out game for us and yeah, it's all in the balance really.

"It's 0-0, we have five points to play with but it's such a small margin.

"The guys have been here loads of times so there is that familiarity as well, but when you're playing for your provincial team and are here representing all those people who have played a part getting these guys running out at the Aviva, that's a huge thing for us.

"So for us it's about delivering a big performance for those people," Cullen added.

"It's a great occasion but the provincial grounds are a bit different, the Aviva is our national ground but it's great more people can go and there are still a few tickets left, it's a great showcase and hopefully we can put on a big show tomorrow.

"It's up to us to throw the kitchen sink back at them as well and defensively be able to shut them down.

"There were a few occasions we looked to be exposed and we've worked hard on that this week, but I'm sure Connacht have been working hard on things as well.”

Leinster – H Keenan; J O’Brien, G Ringrose, R Henshaw, J Lowe; J Sexton (capt), J Gibson-Park; A Porter, R Kelleher, T Furlong; R Molony, J Murphy; C Doris, J van der Flier, J Conan. Reps: D Sheehan, E BYRNE, M Ala'alatoa, D Toner, R Ruddock, L McGrath, R Byrne, C Frawley.

Connacht – T O'Halloran; J Porch, T Farrell, B Aki, M Hansen; J Carty, C Blade; M Burke, D Heffernan, F Bealham; G Thornbury, L Fifita; C Prendergast, C Oliver, J Butler. Reps: J Murphy, D Buckley, J Aungier, O Dowling, A Papali'i, K Marmion, S Arnold, C Fitzgerald,

REF: L Pearce (England)

Leinster v Connacht, Aviva Stadium, 5.30, Live on BT Sport