Said Benrahma's transfer to West Ham is on the rocks after he reportedly failed his medical.
The Brentford star was poised for a £25million move to the London Stadium on domestic deadline day.
But the Mirror now claim that Benrahma's medical has brought back concerning results over blood tests.
The results have been sent back for a second examination, before West Ham make a judgement on what to do.
Brentford insist that nothing is decided yet - and conversations remain ongoing between the two clubs.
It is believed that West Ham are still doing everything in their power to get the deal over the line.
However, it could mean that renegotiations are required over the transfer fee.
West Ham have been pushing the transfer forward following fall outs between Benrahma and Brentford - which were thought to be over finances.
Those issues are said to be resolved, only for the medical to get in the way.
Personal terms are believed to already be agreed in principle.
West Ham now have until 5pm to see if they can get the deal over the line.