Sydney cyclist suffers horrific third-degree burns after his phone explodes in his pocket.

A Sydney cyclist has undergone emergency skin graft surgery after his iPhone 6 exploded in his pocket, causing severe third-degree burns to his leg.

Gareth Clear, 36, fell off his bike while riding around Manly Dam on Sunday afternoon, landing on the phone and piercing its lithium battery.

Within a matter of seconds Clear smelled smoke, felt searing heat and heard an explosion as the iPhone ignited and burned through his shorts, according to The Daily Telegraph.

“I could see the metal bending and all the lithium leaking out of the bottom end,” he told the paper.

Very weird #injury today as my #iPhone exploded on my butt #iphoneexploding #iphonedisaster #iphoneripoff #suingapple #mountainbiking @applefail

A photo posted by Gareth Clear (@garethclear) on Jul 31, 2016 at 12:16am PDT

The Bondi resident doesn’t blame Apple for his injuries, saying the explosion was simply a “random” accident.

“The thing to be very specific about [is that] the phone did hit the ground, it didn’t just spontaneously combust,” he said, according to The Daily Telegraph.

“It was a one in one million chance I hit a part of the phone which pierced the lithium battery and it exploded.”

Apple Australia has not commented publicly on the incident, but a representative has reportedly told Clear the company will launch an investigation.

Featured image: Instagram