Milton Keynes Dons have appointed former Swindon Town head coach Luke Williams as assistant to manager Russell Martin.
Martin was named as the replacement for Paul Tisdale, who was sacked following their defeat by Tranmere Rovers.
Williams, 38, left his previous role as manager of Bristol City's under-23 side earlier on Thursday.
"I hope my experiences assist Russell and I will be doing all I can to help him and the players," Williams said.
MK Dons are 21st in League One, in the relegation zone on goal difference.