England Squash will now have two ElShorbagys as national members after Marwan joined brother Mohamed in switching allegiances from Egypt.
Bristol-based Marwan, 30 on Sunday, will compete under the England flag at all Professional Squash Association (PSA) and World Squash Federation (WSF) sanctioned tournaments.
Marwan, who has claimed 13 PSA career titles, moved to England aged 14. He joined older brother Mohamed at Millfield School in Somerset, training under Jonah Barrington, a six-time British Open champion.
Like Mohamed – who started representing England in June last year – Marwan moved on to university in Bristol and is now a British citizen.
“I can’t explain how excited I am to be representing the English flag next season,” said Marwan.
“I feel I want to start a new chapter of my career by representing England and give something back to the country that’s given me everything.
“England has been my home for the past 16 years. I’ve worked with a lot of British coaches during my career so far, I have had my education in this country and the people have treated me always with appreciation and respect, and that’s why I want to give something back in return.”
Marwan and Mohamed notably contested the final of the 2017 PSA World Championships in Manchester, marking the first time that two brothers had battled it out for the most prestigious title in squash, with Mohamed ultimately claiming the title following a captivating five-game battle.
The following year, Marwan achieved his highest ranking to date of World No.3 and has enjoyed 46 consecutive months inside the top 10 since October 2019.
“My aim is still to get to the top of the rankings, win a world championship and try and win as many majors as I can. I’m only 30, I’m young, and I still have a lot of years left if I take care of my body,” he added.
“I think David [Campion] can add a lot to my game and with his support, and within the system that I have seen my brother thrive in during the past year, I feel confident that I can achieve those things.
“But I also feel I can give a lot back in return within the England set-up – both on the court and around the team environment with junior players. That’s something that I have always wanted to do and it’s something I’m very excited about.”
Marwan will make his first appearance under the England flag at the Paris Squash Alpine next month.
He will also be in contention for the England squad which will compete at December’s WSF Men’s World Team Squash Championships in New Zealand.