While Saracens' tenure at the elite level will take a hiatus after the end of this Heineken Champions Cup campaign, they served notice of their enduring powers in the manner in which they saw off a previously - this season at least - unbeatable Leinster outfit on Saturday.

But why did Leinster struggle, especially in a first half which left them with an eventually insurmountable deficit to make up?

One key area was the scrum and front five according to 2009 Heineken Cup winner Bernard Jackman, who broke down the key issues on this week's RTÉ Rugby Podcast.

For Jackman, the surprise selection of Sean Cronin at hooker ahead of Ronan Kelleher was, in hindsight, a call that did not work out for Leinster.

"I just don't see how they picked Sean Cronin to start. It was a very left field call, particularly given the opposition," he said.

"That's nothing against Sean Cronin but Ronan Kelleher is your best scrummaging hooker and Andrew Porter is still learning his trade as a tighthead.

"So you need to help him against Mako Vunipola, Jamie George and Vincent Koch by giving him the front five around him with the best profile for scrummaging, and for me that's Kelleher and either Fardy or Baird to accompany James Ryan.

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"So you've two out of your front five who weren't as strongly suited to the scrum profile as they should be.

"Against the quality [of Saracens] and the fact that Koch was doing a job on [Cian] Healy and Mako was doing a job on Porter and not having that collective strength of size and power, I think it backfired on them.

"To give up seven penalties in a quarter-final in Europe is nearly unheard of. It was a real long shot that they were going to win the game, even if they were better in the high ball and in the breakdown, because that's enough of an Achilles heel to lose most knockout games.

"So I think selection-wise, big question marks over that."

Aside from selection, certain technicalities also stood out for Jackman in regard to the way Leinster's front row scrummaged.

"There's been a big shift in Leinster's mindset around the scrum," he said.

"The Leinster model was the Irish model under Greg Feek and the scrum was a way of restarting the game. They were more concerned around delivering high quality ball off the back of the scrum to launch strike play rather than hunting penalties.

Maro Itoje celebrates a scrum penalty which went against Leinster

"The Gallagher Premiership, the Top 14, that's where your scrum is seen as a penalty-winning machine or weapon and the last option is to give the ball to the backs.

"We don't have that model in Ireland or haven't had that model in Ireland for the last three or four years. We win penalties every now and again but that isn't the objective as such.

"In fairness to Robin McBryde, he has a different attitude towards the scrum and Leinster wanted to use their scrum as a weapon and when you have a more attacking mindset, it can often open you up to getting a hurt as well and I think that's what's happened.

"They all seemed to be doing different things and not working as a unit and getting involved in individual battles."

Jackman highlighted one example based on overhead footage of the scrum.

"The way Leinster were setting up their scrum, the hooker is prioritising his left shoulder which in theory can push the weight across towards your tighthead which should help Andrew Porter," he explained.

"But I think the best thing to do is use your right shoulder more and bring the hooker down and keep the tighthead out of it. But everyone has their own way of doing things. 

"Effectively, there were too many weak joints in that front five and the back row were paranoid about Billy Vunipola coming off the back, so as soon as any forward momentum came, they popped up and suddenly it was eight against five." 

Listen to the RTÉ Rugby podcast on Apple PodcastsSoundcloudSpotify or wherever you get your podcasts.

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