Scotland head coach Gregor Townsend says “more work” is required to make smart mouthguards “correct” after an alert prompted the temporary withdrawal of prop Zander Ferguson in Saturday’s Six Nations win over England.
Fagerson went off for a head injury assessment (HIA) after six minutes at Murrayfield, with Elliot Millar-Mills taking his place, before being given the all clear to continue.
“Yes it was [an alert] and I saw the tackle again – just a normal tackle,” Townsend said.
“I think we have to really watch what we’re doing here. Trust in technology that’s not been proven.”
Smart mouthguards are being used in the men’s Six Nations for the first time this year.
They record the acceleration force (G-force) and direction of force involved in contacts, known as “head acceleration events”, and can provide real-time data to a doctor or official on the sidelines.
Fagerson is the second Scotland player impacted by the new technology after hooker George Hooker went off the field for an HIA in the defeat by France.
Townsend added: “What we’ve been doing over the last few years is making sure that any symptoms that are seen, a number of people can flag up whether someone goes off for an HIA.
“Zander was taken off for 10 minutes after what looked like a normal tackle but there was a spike alert from the mouthguard.
“I know in Super Rugby there were a couple of alerts and players were saying, ‘there’s nothing wrong here, I’ve just made a tackle’, so we’ve got to watch that because you don’t want to be taking our best players off the field for 10 minutes if there are no issues around concussion.
“We want to protect our players, that’s for certain, but there’s a bit more work to do before this technology is correct.”
Townsend was asked if he believed the technology had been rushed in.
“It’s a new thing in the Six Nations and it’s not been used at club level prior to the Six Nations,” he responded. “I’d hope they’d learn from this incident and obviously George Turner went off for 10 minutes in the previous game.
“[We need] to make sure it’s as close to accurate as possible. That’s what we want.
“We have lots of eyes watching and players are now very good at saying, ‘I’ve had a head injury here, I have to go off’.
“I think we just need to do a bit more work here before we move on.”