The England international spent two seasons on loan with the Blades and played a huge role as the club gained promotion from the Championship in 2018/19, before his excellent form was key in Chris Wilder’s side achieving a ninth-place finish in the Premier League last term.
Dean returned to the Reds last summer following his two-year stint at Bramall Lane, and has played five times for United this season.
Ahead of the stopper's first trip back to his former club, when the Reds take on Sheffield United on Thursday night, Ole was asked for his opinion on Dean’s time at the Blades.