John Breckin has rejoined Rotherham's coaching staff to assist caretaker manager Paul Warne on an interim basis.
Breckin, 63, played for the Millers in the 1970s and 80s and has since served the Millers as assistant boss.
He has been working in the commercial department at Rotherham, but has agreed to help Warne, who was placed in charge after the departure of Kenny Jackett.
Jackett resigned as manager on 28 November after just 39 days at the Championship's bottom club.
Rotherham are 11 points adrift at the foot of the second tier and the 2-1 defeat at Burton on Saturday was their 14th league loss in 19 games this season.
"We first spoke to John last week but I think because it was chaotic I didn't want to bring him in before the game (against Burton)," Warne told the club website.
"Everyone knows him. He is a Miller and he has said he will come in and help me and the club, so I am delighted."