The promising American rider was badly injured in a climbing accident earlier this year

Adrien Costa is back on the bike less than three months after his leg was amputated following a climbing accident.

The former Hagens Berman Axeon rider, who stepped away from cycling in mid-2017, suffered a severe injury while rock climbing in California in July.

While climbing the north ridge of Mount Conness in Mono County, a two-tonne rock gave way and crushed Costa’s leg against a bolder.

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The severity of the injury to the American’s leg left doctors no choice but to amputate.

Now, less than three months after the accident, Costa has returned to climbing and is back on his bike.

Sports marketing agency Corso, which represents Costa, posted a picture of the youngster back in action with the caption: “You can’t keep a good man down.”

Costa had not ridden with his Hagens Berman Axeon team since 2017 after deciding to step back from cycling to pursue other interests.

He proved himself one of the most promising riding talents from the US, winning stages in the Tour of Utah and taking the overall in the Tour de Bretagne in 2016.

Costa also rode as a stagiaire with Etixx-Quick-Step that year.

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After the accident, two hikers were able to alert emergency services which arrived in time to take Costa to hospital and save his life, but the injuries to his leg meant doctors had no choice but to amputate when he arrived at the Renown Regional Medical Centre in Reno.

A fundraising page was set up by Costa’s team to help the youngster in his rehabilitation.

The page raised a staggering $128,000 dollars, with donations coming in from the likes of Roman Bardet, Nathan Haas, Michael Valgren, and Axel and Eddy Mercx.

Earlier this month, Costa posted on Instagram thanking his followers for their support.

He said: “A touch over two months ago I was reminded of the fragility of and impermanence of our existences on this Earth.

“Since I’ve been carried by the support and love from you all, and I realise just how beautiful that makes life.

“Thank you.”