Munster issue 'hands-off' warning to Leinster over one of their hottest young prospects

The Irish Independent understands that Leo Cullen is a keen admirer of the 20-year-old scrum-half and has sounded out Casey's interest in joining Leinster.

Munster have since responded by offering the Limerick native a development contract ahead of next season, with a full senior deal set to be on the table for the following year.

Casey is a major talent and having played a central role in the Ireland U-20s' Grand Slam success this year, his stock has risen, which paved the way for Johann van Graan to hand him his Munster debut off the bench against Connacht two weeks ago.

Despite Leinster being stocked full of scrum-halves, including excellent young pair Hugh O'Sullivan and Paddy Patterson, Cullen is believed to have identified Casey as someone who could add value to his squad.

While player movement between the two clubs has generally been in one direction in recent years, this serves as a reminder that, like everyone else, Leinster are also monitoring the status of young Irish players in other provinces.

Leinster scrum-half Nick McCarthy will join Munster next season as back-up to Conor Murray, but Casey's emergence will create healthy competition.

Like Cullen, Van Graan rates Casey very highly and the Munster head coach wasted no time in securing his future by offering him a development deal before moving to a full professional contract.

"He did brilliantly," Van Graan said after Casey impressed on his recent debut when he was a late call-up to the bench after Murray went down in the warm-up.