Munster coach Johann van Graan has admitted that getting his squad playing together again will be a challenge after the disruption of the World Cup.

Twelve of his players travelled to Japan as part of Joe Schmidt's Ireland squad, who fell at the quarter-final stage, like so many Irish teams before them.

The southern province begin their Champions Cup campaign later this month against Ospreys in Wales. Before that though is their first inter-provincial derby of the season, a clash with Ulster at Thomand Park.

And Van Graan says the game will be used to fine tune ahead of their European opener.

"It was great to see the internationals on Monday morning," he told RTÉ Sport's Damien O'Meara at the launch of the tournament in Cardiff.

"They are raring to go. Pete (O'Mahony) came in and led from the front as our club captain.

"It's great to have the likes of CJ (Stander), Conor (Murray), Andrew Conway, and many more back in.

"The Pro14 is pretty important. We've gone well over the first few rounds, and we'd like to keep that momentum.

"Secondly, it's the first inter-pro of the year against Ulster, who have also gone very, very well.

"From a European point of view you'd like to get some continuity going into that first game, so we'll make sure that we can prepare as well as we can with the limitations that we've had."

O'Mahony's attitude impressed van Graan

Munster reached the semi-final of the Champions Cup last season before falling to eventual champions Saracens.

Van Graan says the depth in the squad will be crucial if they're going to be in the hunt for silverware come the business end of the season.

"It's a different challenge, and it's also an opportunity," according to the Munster coach.

"That's why throughout the pre-season we included all of our academy (players). That's why after the Ospreys game two weeks ago, we could make a lot of changes because we back our squad.

"I can't emphasise enough that you need your squad to perform, week in and week out."