League One side Sheffield United have signed Brentford centre-back Jack O'Connell and Coventry midfielder John Fleck on three-year contracts.
The Blades have paid an undisclosed fee for O'Connell, who made 18 appearances for the Bees after signing from Blackburn Rovers in February 2015.
The 22-year-old had two years left on his contract at Griffin Park.
Fleck, 24, spent four seasons with fellow League One club Coventry and has joined United on a free transfer.
"I'm delighted that the board have backed this signing because Jack is an exciting talent," Blades manager Chris Wilder told the club website.
"John is an outstanding midfield player in League One and we believe he can play at a higher level."
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