A former SAS soldier who faced down brutal enemy fire alongside Ben Roberts-Smith resulting in his prestigious Victoria Cross says the medal became politicised for a "good news story".
The witness codenamed Person Four told the Federal Court on Wednesday the "highlight of my professional career" was that 2010 Battle of Tizak in Afghanistan.
Person Four recalled the war veteran's face looking "ashen" during the raid, and the "absolute feeling of dread and fear" due to the heavy, accurate and sustained fire the troop was under immediately after helicopter insertion.
Under a hail of bullets from two machine guns the comrades decided they would "fight forward" and in concert began "mutually supporting each other enabling us to close with the enemy," he said.
The witness exposed himself to provide "sustained and accurate cover for Ben" who exclaimed "one enemy dead" and later threw a grenade over a wall, that never exploded, he said.
Person Four "100 per cent believed" it was at this moment he successfully killed one of the machine gunners, something he says the decorated soldier later confirmed.
Person Four became emotional on his third day in the witness box, saying the moment stood out "because I didn't let him down".
"And that we both supported each other. And that we overcame overwhelming odds together."
He explained the "gravity" of facing machine-gun power meant a standard infantry would "throw 30 people at it," and "100 people" at more than one such heavy weapon.
"There was only two of us on that day, plus Person 32 ... to overcome those odds ... is why that action is so poignant for me."
Mr Roberts-Smith was awarded the VC in 2011 while his squadmate was honoured with a gallantry medal in 2013.
Mr Roberts-Smith, 43, is suing The Age, The Sydney Morning Herald and The Canberra Times for defamation over reports that he committed war crimes and murders in Afghanistan between 2006 and 2012.
One of a handful of Australian recipients of the VC since 1970, he has suggested some claims stem from jealous associates spiteful of his medallic achievements.
Upon returning home to Australia Person Four said he was initially told he would be receiving the highest honour, but three days later "it changed".
"I was upset something as outstanding as what both Ben and myself did was politicised.
"They could have accepted the fact that both of us did as much as each other that day."
While Person Four does believe Mr Roberts-Smith deserved the award, he suspects other factors played upon "the government and heads of defence".
"2010 (was) the most violent year in the period in Afghanistan, we lost a lot of people and they wanted a good news story.
"I believe people jumped on, or seized the opportunity for their own benefits."
Person Four suspected both soldiers' accounts were too similar, and created a problem due to medal restrictions.
He said the delay of this caused him hurt, disappointment and was something he ruminated over, wanting the recognition for his two children he had left to fight in the war.
But he denied deeply resenting the decorated soldier over the incident.
"I loved him as a brother," he said of Mr Roberts-Smith.
"And now you hate him," Arthur Moses SC on behalf of Mr Roberts-Smith said.
"Of course I don't," he said.
Person Four was medically discharged from the army last year and excused from giving evidence over an alleged execution he carried out at a compound nicknamed Whiskey 108 due to "self-incrimination".
He began giving evidence on Monday of allegedly watching Mr Roberts-Smith kick a handcuffed Afghan prisoner off a cliff in the village of Darwan, Uruzgan province in September 2012.
He denied fabricating the story to diminish Mr Roberts-Smith's reputation.
The trial continues.