Cape Town - Chiefs centre Charlie Ngatai will miss this Friday's Super Rugby clash with the Crusaders in Suva because he developed a headache on Monday.
Ngatai, who returned to first-team action against the Reds in New Plymouth last week, has long been troubled with concussion symptoms.
The Chiefs could not confirm whether the headache was related to those previous issues but as a precaution Ngatai has not flown to Fiji.
"Charlie developed a headache after training the other day," assistant coach Andrew Strawbridge told the New Zealand Herald.
"We're not sure why but we're taking a precautionary approach - that's the reason he's not playing.
"We checked footage and we couldn't see anything that happened at training that might have caused it. It is what it is - a post-training headache - and we want to look after him."
Kick-off on Friday is at 09:35.