French media have revealed the reason Dan Carter failed a medical examination, forcing Racing 92 to pull out of a lucrative three-month contract with the former All Black first-five.
Carter, who left Racing in July last year to join Japanese side Kobe Kobelco Steelers, was signed as a short-term replacement for South African Pat Lambie, who was recently forced to retire after several concussions.
He was expected to join the Parisian outfit on March 10.
Racing announced on Sunday, however, that they had withdrawn their offer on medical advice.
"As part of routine medical checks prior to the approval of players' licenses, Racing 92 forwarded certain medical information to experts appointed by the Ligue Nationale de Rugby (LNR). Their opinion was unanimous: Dan Carter will not be able to play rugby in France," the club said in a statement.