Rotherham United have signed loan centre-half Semi Ajayi on a three-year deal.
The 23-year-old has played nine times for the Millers since joining from Championship rivals Cardiff City in the January transfer window.
Despite mistakes in his last two matches which have led to goals, the former Arsenal youngster has impressed with his pace and strength at the heart of the Rotherham defence.
Caretaker boss Paul Warne said: “Since he has come into the club, he has done really well.
“He always wants to play, even when he has been sore after games. That is the kind of mentality that we want here, I think you can really judge someone’s character from their desire to go through the pain barrier for the team.
“Semi has done well but we are all working hard with him so he keeps improving.”
The Millers are poised to be relegated from the second tier and Ajayi, whose deal runs until the summer of 2020, could be a key man in League One next season.
His contract with Neil Warnock’s Bluebirds, for whom he never made a first-team appearance, was due to expire this summer.