Ollie Marchon will make a poignant England Sevens debut in Dubai this week after a remarkable journey back into the professional game.

The 24-year-old from Hertfordshire was a spectator in the stands in the United Arab Emirates when England lifted titles there in 2010 and 2011 without even daring to dream he could be lining up in the desert as part of the team.

Six months ago he was more likely to be playing against them, holding a qualification for one of Friday's Pool C opponents.

But this week he puts his career as a personal trainer and semi-pro player for National League One side Old Albanians on hold to pull on an England shirt, six years after a knee injury ended his hopes of a senior contract at Saracens and threatened to force him out of the game for good.

"After the injury I went travelling, went to university and for a little while kind of resented rugby and didn't take it too seriously," said Marchon.

"I did my three years at university and then got back into it, moved home, found a good semi-pro club in Old Albanians and we managed to get promoted.

"Last year was my first of trying to play serious Sevens. A teammate of mine asked the coach of the Wailers, who play on the invitation circuit, to have a look at me. I played the first tournament, got invited back, played on the Super Sevens Series this year and it all took off from there.

"I might have played for Portugal - my dad's Portuguese by nationality, my mum's from Nuneaton - then after the last tournament of this year's season [England Sevens assistant coach] Russell Earnshaw approached me about training with England and that's how it came about.

"I'm over the moon about it. I didn't envisage it happening and I'm hoping I take the opportunity."

Marchon's call-up is one of four changes England have made for Dubai.

Scrumhalf James Lightfoot-Brown, 19, is another debutant while playmaker Dan Bibby returns and former captain Ollie Phillips is back after a three-year lay-off.

England face South Africa and Samoa in their other pool games on Friday, before Saturday's knock-out stages in the second leg of this season's IRB Sevens World Series.

The third leg takes place the following weekend at the Nelson Mandela Bay Stadium in Port Elizabeth.

England: Dan Bibby, Chris Brightwell, James Lightfoot-Brown, Ollie Marchon (Old Albanians), Tom Mitchell, Dan Norton, Ollie Phillips, Tom Powell, James Rodwell, Rob Vickerman (captain), Marcus Watson, Jeff Williams.