Growing calls for independent medics in professional rugby are likely to gain momentum, after World Rugby's clampdown on high tackles entered its second week in Northern Hemisphere club competition.
Irish and Munster scrumhalf Conor Murray copped an elbow from a Glasgow opponent in a tackle that left him prone on the ground for several seconds. He was allowed to continue, but moments later, he made a tackle that again saw his head compromised.
Munster medical staff finally removed Murray for a required Head Injury Assessment, but cleared him to return to action.
Former England prop and NBC Sports rugby analyst Alex Carbisiero tweeted:
Murray already has a long history of concussions. He was a marginal selection for the 2015 World Cup, after suffering three suspected concussions in 10 months and was knocked out 16 minutes into Ireland's Six Nations game against England last year.
In another incident under investigation, Sale Sharks and former Highlanders No 8 TJ Ioane also seemed to suffer a head injury in an attempted tackle during Sale Sharks' 29-26 Avia Premiership loss to Harlequins last week. He was subsequently not selected for his club's Champions Cup game against Toulon.
Notably, both Murray and Ioane suffered their injuries as tacklers.
These episodes have taken on greater significance, in the context of a recent high-profile case of Northampton and Wales wing George North being cleared to continue, despite apparently being knocked unconscious.
The new zero-tolerance approach on head-high tackles claimed just one victim, after a flurry of red and yellow cards (and penalty tries) last week.
But the victim was another Irish inside back, Jonathan Sexton, who was blind-sided by South African counterpart Francois Steyn 24 minutes into Leinster's 57-3 romp over Montpellier. Steyn was shown a red card, while Sexton was also allowed to play on, after apparently passing the HIA.
In his second game back from a hamstring injury, Sexton had passed the ball to his back-line, when Steyn took him out with a late, high tackle.
"It felt like a forward," said Sexton later. "When I looked back at the TV, I expected it to be one of their back-rowers.
I know Frans well. He's a good guy and I think it looked like I was ducking down into it a little bit, so it could have been accidental.
"But with these new laws, I suppose you can't afford to be reckless. It probably was a yellow card, now it's a red.
"I felt for him, because he's not a dirty player and it was probably accidental."