US Special Forces agent George Vera was working quickly to secure a small base in Afghanistan stormed by insurgents wearing suicide vests and thought the area was safe.
But less than 40 feet away a pair of fighters had waited for nearly two hours, hidden under a vehicle.
"The worst part was I knew my best friend was dead, but we're taught do what you need to do and we knew we needed to take back the gate otherwise more would get through and detonate their suicide vests," George Vera told AAP.
His best friend had just led a small patrol group to secure the base in Kabul when he was gunned down.
"At that moment training kicks in until either they're eliminated or you're no longer in the fight."
His troop were searching the vehicles, edging closer to the hidden insurgents. When his back was turned they opened fire, hitting him four times - in the ankle, the knee, and twice in the back, shattering his spine.
As he was airlifted by a helicopter to Germany he was brought back to life twice by an Austrian medic.
Following the attack in 2015 months of rehab and after-care saved his life, but he's been paralysed from the waist down ever since.
During the onslaught he exposed himself to pull wounded comrades from the field; for this he would later be awarded the Silver Star, one of the highest honours in US military, as well as other medals.
Before his injuries Mr Vera worked out about four times a day. Training first for the 2018 Warrior Games and most recently Sydney's Invictus Games gave him a reason to hit the gym once again.
"George practicing for these sports doesn't only help him, by helping himself it's also helping me and my daughter," his wife, Angela Vera, told AAP.
"Coming here meeting a lot of people and thinking oh my gosh how are they doing it, it's another way to see the light, and it's a good way, and we are learning together every single day. "
Travelling from Tampa in Florida, Angela and their daughter have accompanied George at the Sydney Invictus Games.
"It's good for my daughter to be here because it shows her she can do anything," Mr Vera said.
After competing in multiple athletics events on Thursday, Mr Vera said the competition was extremely tough, but he's quietly confident his wheelchair basketball team are in with a winning chance.
On Friday morning the US wheelchair basketball team dominated one of the first pool matches of the day, beating New Zealand 31 - 11.
They are scheduled to battle it out again on Friday evening against Canada for a spot in the finals on Saturday.
Australian Associated Press