The Welshman joined the Baggies in 2018 having previously been head of sport science at West Ham, Norwich, Birmingham and Charlton.
An expert in injury prevention, Albion’s record for player availability has been hugely impressive during Davies’ time at the club.
Former boss Sam Allardyce often praised Davies and his team for ensuring Albion’s players were in the best shape to avoid injuries.
Speaking in May, he said: “They keep a very healthy squad here.
“A lot of credit has to go to them because we have had very few problems with injuries.”
But following the arrival of Valerien Ismail as head coach, it is understood both Albion and Davies, who is unlikely to be short of suitors, felt the time was right for a parting of the ways.
The Express & Star understands Ismael is still working to finalise his backroom team. And it is believed he wants to add two coaches to his staff.
It is not known exactly who the head coach is hoping to lure to The Hawthorns.
But he did appoint Joseph Laumann as his assistant manager at Barnsley to work alongside club stalwart Adam Murray.
Speaking last year, Laumann revealed he and Ismael had been friends for several years but had never worked together until their move to Yorkshire.
Ismael is in the UK but is currently quarantining under government guidelines after he returned to Europe following Barnsley’s defeat in the play-off semi-finals.
He will be out of quarantine in time for the first day of pre-season training.
As well as Allardyce, coaches Sammy Lee and Robbie Stockdale also left Albion at the end of last season.