A leading brain injury charity has questioned whether protocols were followed after Manchester United defender Harry Maguire suffered a blow to the head in the opening minute of his side's Premier League victory at Fulham on Saturday.

Maguire went down on his haunches and looked uncomfortable after being caught on the side of the head by Rodrigo Muniz's shoulder during a challenge at Craven Cottage.

He was checked on the pitch for possible concussion by United's team doctor — as per English Premier League guidelines — but allowed to continue, although the England international needed a second check after half-time.

The incident again raised the issue of "temporary concussion substitutes" being introduced, whereby a team could bring on a replacement while the injured player is assessed off the pitch, as they have already in rugby.

"We have come such a long way since Hugo Lloris was labelled a 'hero' for over-ruling club medics to return to the pitch after a clear concussion while playing for Spurs against Everton in 2013," Luke Griggs, chief executive of Headway, said.

"That shocking incident was a wake-up call for football. We called it 'dangerous and irresponsible' at the time, demanding it be used as a catalyst for change.

"But this progress is eroded with every high-profile incident in which the safety first principle is set aside and players being allowed to continue."

There is no suggestion that Manchester United's medical staff did anything wrong, but Griggs said the incident highlighted again the need for concussion substitutes to be adopted across the sport.