The Grand Slam celebrations have subsided, the class of 2018 have drifted back to their provinces, and now - in the words of Peter O'Mahony - "it's back to work".

It's barely a fortnight since that famous win in Twickenham but there's no time to dwell on that for the Leinster and Munster men facing into a huge weekend of Champions Cup quarter-final action.

They face Saracens and Toulon respectively, and O'Mahony admits that the size of the challenge coming Munster's way has quickly sharpened focus levels.

The Top 14 powerhouses warmed up for their trip to Thomond Park with a 49-0 annihilation of Clermont. They mean business.

"The calibre and quality they have throughout their squad, the performance they put in against Clermont... as I said they were always in the back of your head," O'Mahony told RTÉ Sport.

"Now that the week has come, it really settles the mind. It's back to work.

"It's a great competition. To be in the knockout stages, that's where you want to be playing. It doesn't get any bigger than Europe."

Having home advantage certainly helps.

Munster will be banking on the Thomond roar to help them over the line, though O'Mahony concedes that playing ion front of their own fans does put some pressure on the hosts.

They do not want to let them down. And there's a serious threat coming to town. 

He said: "There always is a huge fear factor. Us being at home, in front of our own crowd, against a team with the quality they have... you've got to have a bit of fear in the back of your head of the damage they could potentially do.

"We know the craic. There's a lot of us that have been involved in European Cup rugby for a long time.

"You've got to put huge pressure on yourself to train well during the week, to get all that small stuff done.

"It's not about changing anything big, it's just about performing well during the week to give yourself a chance to play as well as you can. It's a special week; it always is." 

Follow our live blog of Munster v Toulon (3.15pm kick-off) on RTÉ Online and the RTÉ News Now App, or listen to commentary from Michael Corcoran and Donal Lenihan on RTÉ Radio 1's Saturday Sport.