41-year-old Davidson has been at St. Johnstone for five years but was targeted by new Stoke City manager Gary Rowett after he was appointed new Potters boss last month.
Having played together at Leicester City, Rowett knows Davidson very well and sees him as essential part of his new look backroom staff. Former Scotland International Davidson also worked under Gordon Strachan for his national side and has a wealth of experience he can bring to Rowett and Stoke.
Davidson has served Saints as a player and a coach but will continue his coaching career in England in the Championship.
Meanwhile promotion hero from 10 years ago, Rory Delap is also set to return to the club as part of Gary Rowett’s coaching set up according to the Stoke Sentinel. Delap is currently the manager of Derby County’s Under-18s side and Rowett is keen to bring the Irishman back to the bet365 Stadium.
After being relegated from the Premier League last season, Stoke are among the favourites to win promotion back to the elite this season. They have agreed a new four-year deal with Joe Allen and have added Nigeria World Cup midfielder Etebo and promotion winning striker Benik Afobe to their ranks.
St. Johnstone boss Tommy Wright is now tasked with finding a new number two ahead of the commencement of the Scottish Premiership in August.