Turning up to Le Mans in May 2012 the rumours were rife about Casey Stoner considering retirement from MotoGP as defending world champion aged just 26.

The Australian himself previously batted away speculation but during the build-up to the French Grand Prix, fresh from back-to-back wins at Jerez and Estoril no less, he dropped the explosive news that he would retire at the end of the season.

Despite numerous situations which almost led to Stoner’s return, he has never contested a MotoGP weekend since bowing out at the 2012 finale in Valencia.

Stoner’s reasons for retiring so young were put down to falling out of love with the sport, while also grew frustrated at the political powers in the paddock, and he wanted to spend more time with his young family. In subsequent years the two-time MotoGP world champion has also shed light on the chronic illness he had also been fighting while racing.

But rewinding the clock back to 2012, what would have Stoner taken on if he didn’t walk away from Repsol Honda and MotoGP eight years ago?

Much like our previous dive into what could have been with Nico Rosberg in F1, the primary focus is on the subsequent season Stoner left MotoGP given the direct impact his actions had on the campaign.

But trying to guestimate what would have happened beyond 2013 becomes a trickier task due to so many variables which can’t be known.

So, assuming Stoner hadn’t left Honda at the end of 2012, the situation inside the Repsol Honda garage would have looked totally different.

In the years after Stoner’s exit, Honda boss Livio Suppo has explained the Japanese manufacturer was preparing to mould its future MotoGP machines to the Australian’s requirements – a tactic Marc Marquez has subsequently benefitted from over the past few years.

But with only two spots in the team, and Stoner assumedly keeping his place for 2013, it would have meant Dani Pedrosa was under threat from Moto2 world champion Marquez.

Marquez was almost promoted to Repsol Honda 12 months earlier but the call to contest a second season in Moto2 coincided with the Spaniard suffering a career-threatening vision issue when he crashed during practice at the 2011 Malaysian round.

After recovering from the vision trouble over the winter, Marquez duly stormed to the 2012 Moto2 world title making his promotion to MotoGP irresistible. While it can never be taken as a certainty, a Repsol Honda rider combination of two-time champion Stoner and rookie hotshot Marquez would have been incredibly attractive, leaving Pedrosa out in the cold.

Given Pedrosa’s calibre and potential, it is also almost certain he would have found a new spot on the MotoGP grid for 2013. But where exactly becomes a tougher call. Yamaha looked a no-go with the returning Valentino Rossi alongside reigning MotoGP world champion Jorge Lorenzo but Ducati could have been an option following underwhelming results from Nicky Hayden.

If it wasn’t to be a factory seat at the Italian manufacturer, Pedrosa’s only other options would have been a satellite squad given the absence of the likes of Suzuki, Aprilia and KTM back in 2013 and the use of the Claiming Rule Team entries to bolster the MotoGP grid.

Under the assumption Stoner and Marquez form Repsol Honda’s 2013 rider line-up, could the Australian have fought for a third premier class crown? Almost certainly, injuries permitting, given Marquez stormed to the title as a rookie while Pedrosa ended the season in third place only 34 points off his team-mate.

Injuries will always cloud certainties and while Stoner missed three races in 2012 with torn ankle ligaments, he did fight back with two podiums and a victory over the final three races of the year before bowing out.

In their two years as team-mates, both Stoner and Pedrosa beat each other in the riders’ championship but both were aided by the other missing races through injury.

But with Stoner taking a 46.8% win ratio to Pedrosa’s 31.2% across 2011 and 2012 (while Stoner also has a higher points per race average of 18.9 against Pedrosa’s 17.2), the Australian rider appeared to have the edge in a fair fight which would have put him at a higher level against rookie sensation Marquez in 2013.

Between Marquez and Pedrosa, the Repsol Honda squad picked up nine wins in total in 2013 equal to the factory Yamaha team’s nine victories shared between Lorenzo and Rossi.

Stoner could have even tipped the balance towards Honda given his undefeated record at Phillip Island in the Bridgestone tyres era – as Lorenzo claimed victory in Australia that season while Marquez was disqualified from the race in bizarre circumstances.

How Stoner would have dealt with Marquez in MotoGP is a battle fans have been denied as their respective careers narrowly missed overlapping in the premier class. With the duo facing off on equal machinery over a season it would have only heightened the interest and power play within the Honda camp.

Casting any predictions on Stoner’s fortunes further than 2013 becomes inherently more difficult due to two core elements: the rider market transfers and the incoming technical rules overhaul through the arrival of the standard ECU, switch to Michelin tyres, engine development freeze and concession team allowances which came into MotoGP between 2014 to 2019.

Would Stoner have been uprooted by the arrival of Marquez at Honda and preferred a return to Ducati in 2014, as he did briefly as test rider after retiring? And would Stoner have been able to adapt to the rules changes, standardised ECU and Michelin tyres? Being certain on any of this relies too much on events of what could have happened in 2013 and beyond.

What do you think would have happened if Stoner didn’t retire at the end of 2012? Let us know in the comments section below.