Heineken Cup champions Leinster are unbeaten in their last 13 tournament matches, but they face a massive test against French standard bearers Clermont Auvergne in Bordeaux on Sunday - in attempting to take that run to 14 matches without defeat.
A 16-all draw at Montpellier in Round One of this season's tournament is the only time they have not walked off winners since, ironically, they were beaten 20-13 at Clermont in last season's Pool stages.
Now the clubs go head-to-head again at Stade Chaban-Delmas with a prestigious place in the 17th Heineken Cup Final at Twickenham Stadium on Saturday, 19 May, at stake against the winner of the Dublin semi-final between Ulster and Edinburgh.
And it promises to be a fascinating contest in Bordeaux - on the pitch between two star-studded sides and off the pitch between two former colleagues.
Leinster coach Joe Schmidt was with Clermont and alongside Vern Cotter when the French club ended their agonising wait for the French Championship title with the 2010 crown.
And, if it was needed, just to add another dose of spice to the mix Nathan Hines, a Heineken Cup winner with Leinster a year ago, is now looking for the double with Clermont.
"Both teams will be very strong and I just think the biggest winner is going to be European rugby because it's going to be a hell of a battle," said Schmidt.
"Now it's about chasing silverware and it's a hell of a tough task that awaits us on Sunday."
Hines, who is bidding to become one of the elite to lift European club rugby's most coveted silverware with different clubs, admits the collision between his old and his new club was almost inevitable.
"If we wanted to go far in Europe we knew one time or another we would have to cross paths," said Scottish international second row Hines.
"Joe and Vern spent a lot of time together and they will try to out-fox each other so it just comes down to the day.
"Leinster are pretty much the same team as last season and I think the teams are quite similar with effective forwards and good back rows. On paper you're looking at a 50-50 game."
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