Euan received a blow to the head a month ago while playing against Munster but had been passed fit to play last weekend against Llanelli Scarlets. "He suffered a recurrence of the symptoms, and with an injury like that you do not take any risks," Hugh Campbell, the Glasgow coach, said in The Times. "The medical advice is that this does happen, especially after taking heavy exercise, and is nothing to worry about, but we will not risk playing him."
Hugh also said to the Daily Record: "He passed all relevant tests in the build-up to the game but exertion can cause this to happen. I must stress that he was not at risk and it is not a case of him being back to square one.
"There's no major trauma it's just that there have been signs he is not 100 per cent."
Gerry Haggerty, the team doctor, confirmed they are merely being ultra-cautious, with player welfare being prioritised even at a time when resources are stretched to the limit.