Sheffield United have signed Brentford captain John Egan for an undisclosed club-record fee on a four-year deal.
The 25-year-old defender scored seven goals in 71 games during two seasons with the Championship side, following a switch from Gillingham.
The Republic of Ireland international, capped twice by boss Martin O'Neill, had a previous one-game loan stint with the Blades from Sunderland in 2012.
"John has been our number one target in that position," boss Chris Wilder said.
"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."
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