James O'Connor suffered a heart attack on the bus home from Toulon's win at Oyonnax last Sunday.
Midi Olympique reported the utility back was rushed to hospital to undergo tests following initial 'treatment' from team-mate Mamuka Gorgodze upon the team's return to Toulon.
The club is yet to make an official comment on the health of O'Connor, who is expected to be sidelined for some time.
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