West Brom have cancelled the Senegalese forward's transfer to the Hawthorns as the player has a muscular injury in his back.
Sakho missed a lot of last season due to a thigh injury, but the striker is set to spend more time on the sidelines with this latest problem.
However, history may repeat itself with respect to Tony Pulis' side and failed medicals. Demba Ba famously failed a medical at Pulis' former club Stoke, ended up joining Newcastle and scored a hat-trick in a 3-1 victory over the Potters.
Let's see if Pulis will be haunted by the case of the failed medical once again.