LIKE wearing a half-half scarf, changing a team’s kit colour is considered treasonous by many football fans.

Supporters identify with their team’s colours — whether it be the all-white of Real Madrid, the old stripes of Barcelona or the technicolour combinations of Brazil and Spain from years gone by.

But in recent years the playing colours of international football teams have undergone a gradual shift which, until now, the Socceroos had avoided.

On Tuesday, the Socceroos’ new banana-gold home kit was unveiled, alongside a similarly standardised dark blue away strip. The Matildas will wear identical colours.

The move by kit manufacturer Nike to bring in all-gold and all-blue strips follows the lead of rival sportswear company Adidas in introducing monochrome kits to international football.

Trent Sainsbury and Aaron Mooy in the new Socceroos home strip. Source: Supplied

Complete with all the mod cons that increase ventilation and reduce fabric weight and sweat retention, the Socceroos’ new kit is at the forefront of modern athletic apparel.

But that is of little concern to fans who have been asked to identify with new colour combinations or in many cases, the removal of one of more colours from the shirt-short combo.

While much criticism has been directed at the likes of Adidas and Nike, few realise that the manufacturers of international kits have been left with little choice.

Before the 2014 World Cup in Brazil, FIFA introduced a rule — specifically, Rule 2, Section 35 of the playing regulations — which states:

“Each team shall inform FIFA of two different and contrasting colours (i.e. strips). One predominately dark and one predominately light for its official and reserve kit.”

The new Socceroos and Matildas away strip. Source: Supplied

As the Daily Mail’s Sheridan Bird explained at the time, “FIFA believe lights v darks help the referee clarify tussles, lunges, tackles and deflections. They don’t ask teams to wear one colour, but Adidas, as an official partner of the governing body, followed the rule closely. Hence Germany resembling Leeds and Spain doing their Bayern Munich impression.”

At their home World Cup, Nike-sponsored Brazil were never going to follow the regulations to the letter of the law but their blue shorts did soften slightly to qualify as ‘light’.

But now fellow Nike nation Australia have taken the plunge, dropping the bottle green shorts for an all-Gold strip that has left fans miffed.

While green will remain the colour of the home socks, its notable absence will take some getting used to for seasoned Socceroos observers.

The reaction following the Socceroos’ kit launch on Tuesday was predominantly less than positive.

@Heathypiper @Socceroos that FIFA rule on shorts and shirt being the same colour is ridiculous. — Neighbourhood Volt (@cue_volta) March 22, 2016

Must say it's great to see the @Socceroos and @matildas going with the dark blue away strip. Unique to Australian sport. — Patrick Galloway (@pat_galloway1) March 22, 2016

Not enough green on the new Socceroos kit. Looks too much like a CCM kit. #Soceroos — Ben (@Dyssius) March 22, 2016

Yellow shorts going a long way to prove Nike are having a shocking year for kits #socceroos — Bill Molloy (@Bill_Molloy94) March 22, 2016

Death, taxes, and people complaining about Socceroos jerseys. — Adrian (@ad_roq) March 22, 2016

Not enough green on the new Socceroos kit. Looks too much like a CCM kit. #Soceroos — Ben (@Dyssius) March 22, 2016

But as Bird pointed out back in 2014, should success follow a change to a time-honoured colour combination, fans will quickly forgive the sins of the football hierarchy.

“Barcelona debuted ground-breaking red shorts in 2005/06 and supporters were horrified. They quickly forgot when Ronaldinho and pals wore the offending items to Champions League glory,” he wrote.

“Of course, this mild outrage is nothing compared to the apparel armageddon on the horizon. Wait until FIFA propose sponsors on national team shirts …”