Reading manager Brian McDermott says his assistant Terry Burton chose to leave the club after just 14 days to focus on a "new project".
Former AFC Wimbledon boss Burton left his post at the Royals over Christmas after three games.
McDermott moved quickly to replace Burton with first-team coach and former Reading academy graduate Chris Davies.
"I don't really need an old head around me, I've got my own old head," McDermott told BBC Radio Berkshire.
"Terry has got a project that he wants to take care of and he's a good man who I've known a long time. But, I'm delighted to welcome Chris to the club.
"He has done a lot in a short space of time and I'm pleased to have him here."
Davies worked alongside former Reading manager Brendan Rodgers at both Swansea and Liverpool, who he first played under as a youth player at Reading.
"I've got two young coaches around me now," McDermott added. "There's loads of enthusiasm from Chris and Steven Reid and I'm happy with the staff and what we have done."