Eintracht Frankfurt captain Marco Russ has been diagnosed with a tumour after he had initially tested positive in a routine doping test, the Bundesliga club said on Thursday. The club were informed of the positive test on Wednesday with Germany’s anti-doping agency (NADA) suspecting that the high levels of growth hormone HCG found in the sample were due to illness rather than the use of performance-enhancing drugs. Further tests by the club revealed they were indeed due to a tumour, Frankfurt said, without disclosing the location of the growth.