Anthony Joshua has revealed how his boxing career almost went up in smoke following a drugs conviction in 2011 – and how a subsequent painful loss rekindled his passion for the sport.

Joshua is completing preparations for the so-called ‘Clash on the Dunes’ in Diriyah as he looks to regain the world heavyweight titles and reverse his stunning loss to Andy Ruiz Jr in June.

The 30-year-old was initially kicked off the Great Britain squad after admitting possession of cannabis – then suffered a stoppage defeat to Mihai Nistor at the European Championships within weeks of being invited back.

Joshua told the PA news agency: “After I got kicked off the GB squad I went back to Watford and started smoking again and tried to forget all about boxing. I thought – and I could use different language – ‘This is nonsense’.

“Then two weeks before the Europeans they called me up and said, ‘We want you to compete’. I got to the quarter-finals and got stopped, but I knew if I’d been fit I would have beaten the guy.”

Four months later Joshua suffered another defeat in the World Championship final to Magomedrasul Medzhidov, who is scheduled to fight Hatfield’s Tom Little on the Saudi Arabia undercard.

But in many respects his single-point reversal in the Azeri’s home city of Baku proved the making of Joshua, who had also scored a notable win over double reigning world champion Roberto Cammarelle in the quarter-finals.

“I got myself fit and ready for the worlds and got beaten by the Azeri in Azerbaijan,” recalled Joshua.

“The Olympics were coming up in London and being a Londoner I told myself I was going to win that.”

Joshua’s third and final amateur nemesis, Dillian Whyte – whom he subsequently went on to beat as a professional – is also set to appear on the Saudi card.

Despite that reversal coming in a novice contest in 2009, Joshua maintains there are lessons from that fight which linger and have continued to inform his attitude during his rise to superstar status.

“I had won my first two fights as an amateur by knockout, so for my third one I told all my boys to come and I got knocked down, so I thought, ‘F*** that, I’m going to keep it low-key’.

“There’s nothing wrong with taking losses – it’s just an experience and you learn from those situations.

“If you correct your wrongs and don’t shy away from them, you can always bounce back.”