He urged Steve Borthwick to raise the issue before the game.
Gatland wrote: “If I was Steve, I would be asking some questions about the number of head injury assessments that South Africa called for in their victory against France.”
However, he stopped short of suggesting the assessments weren't genuine.
He added: “I am not questioning whether they were legitimate or not.”
Gatland nevertheless believed England should flag what they had seen, adding: “I would certainly be putting it out there and highlighting that it looked unusual and raising questions about the protocol.”
'After Rassie Erasmus was spotted with details of our tactics I was told we were being filmed from a house overlooking our training pitch'
✍️ Warren Gatland
Read his full column below 👇
telegraph.co.uk/rugby-union/20…