National midfielder Chiu Chung-man could lose his place with Sing Tao in the new season as he is struggling to meet fitness levels set by the Hong Kong Football Association.
Chiu, who joined Sing Tao from Golden in the off-season, must improve if he is to meet the minimum standard of running 3,000 metres in under 12 minutes.
Those who fail the test will not be able to register to play in the elite league.
During the Tigers' training on Wednesday, where players had to run 350-metre laps in under a minute each, the 27-year-old Chiu could only finish 5.5 laps - with a three-minute break between each lap.
Sing Tao coach Sin Tik-hung, and even Chiu himself, think he could fail the crucial HKFA test.
'I am really struggling. I am nowhere near the standard,' said Chiu.
'If I have to take banned drugs to pass the test, I will take it,' he desperately added.