Peter Hartley has signed a permanent contract until summer 2020 with Motherwell after spending six months on loan from Blackpool.
The 29-year-old English central defender has made 17 appearances for the Scottish Premiership club.
Manager Stephen Robinson told his club website: "Securing the future of Peter is a massive boost to this club.
"As soon as the opportunity came up to get him on a permanent deal, we wasted no time in getting the transfer done."
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Hartley, who has played for Sunderland, Chesterfield, Hartlepool United, Stevenage and Plymouth Argyle, joined Blackpool from Bristol Rovers in June, signing a two-year contract.
But, frustrated at starting the season on the substitutes' bench, he moved to Fir Park on loan two months later and has now made the move permanent.
"It was a very, very easy decision to make," Hartley said. "I've been at this club for six months and it's a fantastic dressing room, probably one of the best I've been in.
"It's a club that's trying to move forward and achieve things. I want to be part of that.
"I've got nothing but good words to say about the coaching staff and everybody around the club.
"It's just the right place for me in my career right now."
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