The 33-year-old was a bronze medallist at the 2014 Commonwealth Games in Glasgow over 5,000 metres.

He tested positive for EPO during the Great Manchester Run in May, which was confirmed after B-sample testing.

His attempt to submit fraudulent documents to defend himself then led to him facing another charge.

Robertson reportedly claimed he had attended for a COVID-19 vaccination in Kenya, but was instead mistakenly injected EPO as he was treated for the virus instead.

He is said to have submitted hospital notes to back up his claim but Drug Free Sport New Zealand (DFSNZ) found the story to be false.

Dr. Stephen Ritchie, an expert in infectious diseases, spoke about the "clinical implausibility" of the medical treatment said to have been administered in Kenya.

"I asked for a COVID-19 vaccine, but I instead received treatment for COVID-19 (which included EPO)," Robertson said in a witness statement, according to Stuff. 

"Having asked for the vaccine, there was no reason for me to believe that what I was being administered was not the vaccine."

New Zealand Olympic Committee chief executive Nicki Nicol released a statement following the ban.

"The offences committed by Zane Robertson are deeply disappointing and his actions go against everything the New Zealand team stands for," said Nicol.

"We condemn all forms of doping. 

"Every athlete has the right to compete on an even playing field and Robertson's actions have undermined the integrity of sport.

"We thank Drug Free Sport New Zealand for their commitment to supporting the New Zealand athletes who are proud to compete cleanly."

Pete Pfitzinger, the chief executive of Athletics New Zealand, added: "We strongly condemn all forms of doping in our sport and as a supporter of the World Anti-Doping Code, we reiterate our strict anti-doping stance.

"We provide anti-doping education via our national anti-doping organisation, DFSNZ, and we fully support the testing protocols in our sport to ensure a level playing field for all. 

"As an organisation we take athlete welfare very seriously, so we understand the anxiety and stress that Zane will be experiencing. 

"As soon as he received notification of the positive test for EPO last year, we offered and have provided extensive well-being support alongside High Performance Sport New Zealand and we will continue to provide support during this challenging time. 

"We appreciate DFSNZ’s consideration of the athlete's well-being throughout this process."

Nick Paterson, the DFSNZ chief executive, expressed disappointment in the actions of Robertson.

"Doping denies clean athletes the chance to excel on a level playing field," said Paterson. 

"Mr Robertson's actions are not just deeply disappointing, but undermine the high levels of sporting integrity we see and expect from athletes who represent our country.

"This case benefitted hugely from the sharing of key information and the invaluable support of the Athletics Integrity Unit and Anti-Doping Agency of Kenya. 

"Our global partnerships allow us to collaborate across the anti-doping landscape to detect and deter doping and hold dopers to account, wherever they may be."

Paterson also added that anyone who trains Robertson during his suspension will also risk being banned themselves.

Robertson was training in Kenya in anticipation of competing at the Paris 2024, which would have been his third straight Olympic appearance.