 Krehl inspired Morawitz in his studies of blood-related pathology.In 1907 he completed a dissertation on blood circulation (for his Habilitation), and he was appointed in the same year as chief clinician of the University clinic at Freiburg im Breisgau.He progressed to become the "Ordinarius" and Director of the Medical inpatients at Greifswald in 1913, and in 1921 he took up a position in Würzburg.