Ireland international John Egan is on the move after Sheffield United broke their transfer record to sign the defender.
And his fellow international and Cork native Colin Doyle has joined Hearts.
The Blades have spent a reported £4million to sign Egan from Championship rivals Brentford.
"He's a great age, will develop with us and when that happens I have every confidence that he will be a regular international with the Republic of Ireland," said boss Chris Wilder.
"We see him as a leader and he is worthy of the fee we've paid for him. In my opinion he is a better player than a couple of those who have already moved for bigger fees this summer. "
Hearts swooped to sign Doyle after his release by League One side Bradford.
Meanwhile, Southampton have handed professional contracts to Irish youngsters Sean Brennan and Kameron Ledwidge, on deals that keep them with the Saints until 2021.