Standing up, the Iranian Paralympian measures eight feet one inch, making him the tallest athlete in the history of the Paralympics and the joint second tallest man in the world.
At eight feet two inches, only Turkey's Sultan Kosen is taller.
While his height has caused Mehrzadselakjani -- known better as Mehrzad -- anguish and suffering his entire life, on the sitting volleyball court it has made him a star.
When he was substituted on in the third set of Wednesday's group B match against Ukraine, the crowd at the Riocentro Pavilion exploded.
Playing as the setter, Mehrzad served and spiked the team through to match point, when he smashed an ace that sealed Iran's victory in straight sets 22-25 26-28 20-25.
His addition to the team this year, already ranked no. 1 in the world, has strengthened Iran's bid for gold -- the Iranians have won five gold and two silver medals in the sport's seven Paralympic appearances.
But Mehrzad's competitive advantage has come at a hefty cost. He suffers from acromegaly, a rare condition caused by excess growth hormone.
At the age of 16, he already measured over six feet two inches. A year earlier, a serious pelvis fracture from a bicycle accident stopped his right leg from growing -- it's now six inches shorter than the left, making it difficult to walk. Mehrzad normally uses a wheelchair or crutches to get around.
A recent study has shown
that due to increased risk of cancer and cardiovascular issues, people with acromegaly are likely to suffer an earlier death.
Before finding sitting volleyball five years ago, Mehrzad's life was very different.
"I was alone, I was depressed," he told Iranian TV about his life growing up. "But my life has changed from playing sitting volleyball and being a Paralympian."
A coach saw Mehrzad on television and immediately spotted his potential. After training at regional Iranian clubs, he was selected for the national team this March and prepared for his Paralympic debut.
"We have given him the platform to be Paralympic champion," coach Hadi Rezaeigarkani told the Rio 2016 website
. "We are preparing him to make history."
As was the case against Ukraine Wednesday, Mehrzad's first Paralympic appearance was as a substitute in day four's preliminary match with China.
While he was only on court during the second set, the Paralympian made his impact with a killer serve that eased the team towards its resounding victory.
Step by step
"We're not going to show all our cards at the same time," coach Rezaeigarkani told Rio2016.com
about the team's not-so-secret weapon.
"We are going step by step, but we are training him to be the best in the world in two years' time.
"He used to be considered just as a strange guy and now he can be a champion."
Iran's men go through to play the host nation in the semifinal Friday, while Germany play defending champions Bosnia and Herzegovina in the other semifinal clash.