England star cyclist Matthew Richardson has withdrawn from the Commonwealth Games and a spicy clash against Australia — the country he represented at the Olympics.

Richardson controversially switched allegiances to Great Britain, just days after winning two silver medals and a bronze for Australia at the 2024 Olympics.

The shock defection laid the platform for one of the biggest showdowns of this year’s Games with Richardson set to compete against his former teammates for the first time.

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But England confirmed Richardson has been forced to withdraw due to an injury suffered while competing in Japan’s prestigious keirin series.

It’s understood that Richardson crashed out of a race during the series. There was no immediate word on how badly he was hurt.

“Unfortunately, due to an injury sustained in international racing earlier this week, Matt Richardson will no longer be able to compete for Team England at the Glasgow 2026 Commonwealth Games,” Team England said in a statement.

“We wish him a speedy recovery and look forward to seeing him back on the track soon.”

The withdrawal robs the Games of one of the spiciest rivalries in world sport.

Richardson had stirred the pot in interviews over the last few days, saying the Australian track program was like high school and, by comparison, the powerful British system was Hogwarts.

He would have competed in the team sprint when the track program starts on Thursday night (AEST).

But the big showdowns would have come in the match sprint and keirin, where Richardson and former Aussie teammate Leigh Hoffman were the top favourites.

“The Aussies want me to smash him, the Brits want him to smash me and that’s the way it goes,” Hoffman said when the Australian cycling Games team was announced.

While Richardson has competed against Australian riders since his shock move, this would have been easily the highest-profile event where he was to go up against his former teammates.

The men’s team sprint will be one of the first gold medals to be decided in the four-day track cycling program at Glasgow’s Sir Chris Hoy Velodrome.

Richardson, Hoffman and Matt Glaetzer, who has retired, won Australia a breakthrough bronze medal in the team sprint at the Paris Olympics.

Richardson then won sprint and keirin silver, behind Dutch great Harrie Lavreysen.

Matt Richardson changed allegiances after winning three medals at the the Paris Olympics. Credit: AAP

Richardson had said in Paris that his goal was to succeed Lavreysen as the No.1 men’s sprinter by the Los Angeles Olympics.

Days later, he blindsided AusCycling by announcing his career would continue as a British cyclist.

Richardson’s strong form has continued since the controversial move, including two wins over Lavreysen earlier this year at the European championships.

The four-day Games track cycling program starts on Thursday night (AEST) at Glasgow’s Sir Chris Hoy Velodrome, with the men’s team sprint one of the first gold medals to be decided.

— With AAP