bayern munich doctor hans-wilhelm muller-wohlfahrt quit this week .
his resignation came after pep guardiola blamed defeat by porto on injuries .
the pair fell out as early as november over the treatment of philipp lahm .
guardiola now has even more power and could stay at bayern for a long time .
manchester city want to bring him in as manager but he is unlikely to leave .
guardiola , who is impatient with injuries , could even agree a new deal .
former barcelona boss has denied a rift with his medical staff this week .