Bayern Munich and Germany doctor Hans-Wilhelm Muller-Wohlfahrt has launched a scathing attack on Pep Guardiola in a recently published autobiography.
In excerpts published by Bild this week, the medical guru describes Guardiola as 'someone with weak self-confidence' who 'lives in fear of losing authority'.
Perhaps world sport's most famous medical professional, Muller-Wohlfahrt has treated an incredible range of athletes, including Usain Bolt, Darren Gough and Paula Radcliffe.
His relationship with Guardiola, however, was less than harmonious, and got progressively worse during Guardiola's three-year tenure at Bayern.