'Still growing': World's tallest athlete blows minds at Paralympics

Iran has a not so secret weapon at the Paralympics in the form of Morteza Mehrzad, who at a staggering 246 centimetres, is the second-tallest human on the planet.

The towering eight-foot-one inch sitting volleyball star has taken the Games and the world by storm, and it's easy to see why.

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Mehrzad, who is more than 40cm taller than the height of a standard door in Australia, was diagnosed with acromegaly at a young age, meaning his body produces too much growth hormone.

The world's tallest athlete and equal second-tallest living human behind Turkey’s Sultan Kösen, fell off a bike and fractured his pelvis when he was 16 in an accident that caused his right leg to stop growing.

The accident has left his left leg some 15 centimetres longer than his right, meaning Mehrzad requires a walking stick to get around.

Muhammad Ali Dahestani has featured Mehrzad on his disability sport show but revealed that the star's condition doesn't bode well for his future.

“His health is not going well. His health is currently declining because he’s getting taller. I think he’s still growing,” Ali Dahestani said.

“The first time we saw him he could walk better but now he has to walk with crutches.”

However, his unparalleled height advantage makes him a powerful force in an Iranian men's sitting volleyball team that's claimed six of the last eight gold medals at the Paralympics.

Iran national coach Hadi Rezaei discovered the star on a TV program in 2011 that highlighted people with unique talents and physical impairments.

“It is my duty as a coach to discover players, to find talents and teach them,” Rezaei said this week in Tokyo.

Sport transformed Morteza Mehrzad's life

Mehrzad said taking up sitting volleyball helped transform his life after admitting that his condition left him battling depression.

“Due to my impairment I was very depressed,” Mehrzad said.

“I felt like I was in prison and was afraid to go outside due to my appearance. I could never imagine such a future for myself.

“Sitting volleyball has had an immense impact on my life.”

Mehrzad's presence on the court has also had an immense impact for Iran, with the player's incredible reach advantage a constant threat for rival teams.

“We have to sit shorter to the net because of the angle he can hit and that’s how we can defend some spikes from him,” German player Florian Singer said.

Mehrzad has a highest recorded block reach of 1.96m while sitting at the net, while he's capable of extending to 2.30m for spiking - when his team is on attack.

It's those sorts of extraordinary statistics that saw Mehrzad help Iran to a gold medal in the Rio Paralympics and his country is on track to repeat the feat in Tokyo.

Iran have already won through to the semi-finals but the coach insists the team's success is not just down to one man.

“I don’t consider one player the best, I consider them a team,” Rezaei said.

“Morteza is not finished improving yet. He needs more time to improve and become a more complete athlete.”

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