Cast your mind back to August 2022. Tottenham defender Cristian Romero tugged back Chelsea’s Marc Cucurella by his hair.

The VAR, Mike Dean, opted not to intervene for an obvious red card.

It created a line in the sand. From that point on, a zero tolerance approach was adopted.

Has the hair been tugged? Then it is a red card for violent conduct.

A strict application means we have to accept that there are cases, like Keane and Martinez, where the punishment appears too severe.

It is a bit like handball in the Champions League. People do not like some of the penalties, but they know what they are getting.

If you want consistency then you cannot have common sense too.

After the Keane red card, referees’ boss Howard Webb was very clear that hair pulling was “quite an offensive thing”.

“It was the appropriate outcome,” Webb said. “It was unusual but if we see it again next week it will be the same outcome.”

It took a few months before we did see it in similar circumstances with Martinez, and Webb was proved to be correct.

There has only been one other VAR red card in the Premier League, for Southampton’s Jack Stephens on Cucurella.

There have been several other instances in the Club World Cup, Women’s Super League and Women’s Euros.

Hair pulling is one of those dark arts which is usually only spotted through video evidence.

It happens off the ball but is more identifiable than the subtle elbow to the chest or a nip to the stomach.

Even in the EFL, which does not have VAR, Ipswich’s Leif Davis was recently banned after being picked up on camera pulling the hair of Leicester’s Caleb Okoli.

Evidence is not always clear, however.

Fulham’s Kenny Tete could have been sent off for yanking the hair of Manchester City’s Antoine Semenyo in February. It may well have happened, but the VAR did not feel the evidence was conclusive enough for a review.