SATURDAY 19 SEPTEMBER
Leinster v Saracens, Aviva Stadium, 3pm
It's the only show in town for Saracens and it has been ever since they were relegated to the Championship because of the salary cap issues. What you have here are two teams who between them have won the last four Heineken Champions Cup - Saracens have won three of those and those successes were achieved around an incredible strength in depth in their squad.
They don't have that strength anymore for a variety of reasons but they have retained a core of seasoned internationals like Maro Itoje, Jamie George and the Vunipola brothers.
They will put it up to Leinster but I think they no longer have the quality off the bench that is available to Leo Cullen and Stuart Lancaster.
Saracens will bring an emotional energy to this game for all kinds of reasons. If they lose, they won't feature in European competition for at least two seasons, so there is a huge amount at play for them.
I expect Leinster will have too much.
SUNDAY 20 SEPTEMBER
Toulouse v Ulster, Stade Ernest-Wallon, 12.30pm
Ulster are scratching their heads a little bit. They actually played quite well against Leinster. Toulouse are back as a European force and have a lot of quality players on show - seasoned All Blacks in Charlie Faumuina and Jerome Kaino and French half backs Antoine Dupont and Romain Ntamack.
I think they'll have too much for Ulster. They are gone back to their smaller stadium in the Stade Ernest-Wallon and will have 5,000 supporters to cheer them on.
Toulouse have targeted this - they want to make another European semi-final.
Unfortunately it will be a step too far for Ulster.
Donal Lenihan was speaking on Morning Ireland
Follow the Champions Cup quarter-final between Leinster and Saracens (3pm Saturday) with our live blog on RTÉ Sport Online and the RTÉ News app or listen to live commentary on RTÉ Radio 1.
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