Corey Harawira-Naera's will miss at least 4-6 weeks following his seizure on the field, with the Canberra Raiders star back in Sydney for further testing on Tuesday.
The medical thinking around what caused him to collapse with 14 minutes remaining in the 33-26 win over South Sydney on Saturday was shifting towards being concussion related.
But at this stage there's no concrete answer, although it could be the accumulation of Harawira-Naera's previous two hit-ups and a tackle he made before that.