Derby have completed the signing of Barnsley skipper Jason Shackell for an undisclosed fee.
As revealed by skysports.com earlier on Tuesday, Derby had won the race to sign the 27-year-old.
Rams boss Nigel Clough was delighted to land Shackell on a three-year deal to become the club's sixth signing of the summer.
"Jason brings leadership and experience qualities to Derby County and it's a tremendous signing for us," Clough told the club's official website.
"We've had to beat off stiff competition to land his signature and we believe he will have a big part to play in our coming season and our future.
"He's in the prime of his career and was Barnsley's standout player last season, as well as being one of the most impressive defenders in the Championship. Having watched him a lot last season it's clear he's a player who lives to defend."