MULTI-21. Even five years on, the mention of Red Bull’s clever coded word for team orders evokes strong memories.

The ‘21’ bit referred to the order the team’s two cars were supposed to finish the 2013 Malaysian Grand Prix, a race they dominated from start to finish - the No.2 belonging to race leader Mark Webber, the No.1 to Sebastian Vettel in second place.

‘12’ was how they actually finished, Vettel forcing his way past Webber in the closing stages to take away what would have been the Australian’s final Formula 1 win.

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“Multi-21, Seb. Multi-21!” Webber shouted at his teammate in the pre-podium waiting room.

The podium ceremony was just as awkward; Vettel trying his best not to celebrate a win he wasn’t supposed to have, Webber unwilling to even acknowledge his teammate’s existence.

At the time it seemed merely like Vettel disregarding a team order to claim the glory for himself.

It ran far deeper than that.

It was revenge.

Team principal Christian Horner has revealed Vettel’s motivation for the mugging in Malaysia stemmed from the last race of the previous season.

Vettel (far right) was lucky to make it through Lap 1 of the 2012 title-decider. Source: News Limited

“Sebastian was fighting (Fernando) Alonso for the championship and Mark squeezed him up against the pit wall in Brazil in the championship decider,” Horner told Beyond the Grid, the official F1 podcast.

“That ultimately resulted in (Vettel) getting turned around by Bruno Senna. Sebastian was hugely angry about that...”

Horner wasn’t too rapt, either.

“Because we discussed it before the race, that Mark wasn’t in the championship - do everything possible to support your teammate.

Vettel drove back through the field to finish sixth, enough to clinch the title. Source: Getty Images

“But then there was a hangover of that that led into Malaysia. Literally two races later, split by about four months.

“So then you’ve got a situation where Mark’s in the car ahead, Sebastian on new tyres in the car behind.

“The tyres were pretty fragile, we’re telling them ‘right, hold position’ ... and Sebastian thought ‘f*** you.’”

Horner affirmed Vettel saw Malaysia as a payback for Webber’s actions in Brazil, ones that nearly cost him his third world title.

“100 percent, 100 percent. (Sebastian) told him that when they sat down in China. That was probably about as tense as it could get,” he said.

If looks could kill... Webber’s face says it all in the post-race press conference. Source: Getty Images

‘I HAD TO TRY AND EXPLAIN MULTI-21 TO THE QUEEN...’

Vettel became Public Enemy No.1 in Australia, his ‘theft’ of the win and Webber’s rage making headlines around the world.

The Webber-Vettel fallout was the top rating story on foxsports.com.au that entire week - against the early rounds of the NRL and AFL seasons, no less.

It turns out the interest in the saga ran all the way to the top of the British Empire.

Fresh from reading his drivers the riot act back at Milton Keynes, Horner had a royal appointment at Buckingham Palace.

“I’d been invited to a lunch hosted by The Queen and the Duke of Edinburgh,” he said.

“I expected there to be about 200 people at, and there turned out to be 10 of us there.

“I had this bizarre situation of having to deal with the drivers, and then go to lunch with the Queen and Prince Philip and explain to her what a ‘Multi-21’ was and why our Australian driver was particularly grumpy with our German driver.

“I had that conversation over lunch with the Queen! She seemed to show great interest in it and likened it to horse racing.

“And Prince Philip was incredibly interested as well, because he was enquiring whether we could have a look at one of his carriages (to make it go faster).

“It was a most bizarre situation.”

Webber and Vettel were teammates for five seasons, from 2009 to 2013. Source: AFP

‘WEBBER WAS A RUTHLESS COMPETITOR’

As the boss throughout Webber’s time alongside Vettel, Horner has a unique position to analyse how the two shaped up against each other.

He believes there was one fundamental, unavoidable truth about their pairing that drove Webber to try and destabilise Vettel in response.

“I think it was very difficult for Mark to accept at the time - and if I think he looked back at it now with perspective and honesty - Sebastian was just quicker,” Horner said.

“So therefore Mark would use whatever tool he could to get under his skin. Because Mark was a great competitor, he was a ruthless competitor. He’d read every mind-management book in the business. One of his heroes was Roy Keane!

“Mark would use whatever tool he could to try and ruffle Sebastian, and if that meant using the team to do that, he would do that.

“Mark drove some fantastic races. On his day, there was Monaco 2010, Barcelona that year, Nurburgring 2009, Silverstone 2011, he drove some phenomenal grand prix where he was untouchable

“But what I think Mark struggled with was maintaining that level.

Webber’s car is loaded up after crashing out of the 2010 South Korean Grand Prix. Source: AP

“His best chance, in 2010, leading the world championship in Korea in the wet ... he’s pulling away a second a lap from all the cars behind him.

“But he was so obsessed by Sebastian pulling away ahead of him (that) he dropped the car. And that was a fantastic chance for him to win that world championship.”