He and the victim were away together at a tournament in Wellington.
When they returned to Auckland they went to a party with other players and friends, then into the city to continue drinking.
The court heard that the victim was heavily intoxicated and had consumed recreational drugs.
He started throwing up outside a bar and a friend decided to take him home.
Gibbons joined them.
They got back to the friend's house and put the victim to bed on a mattress in the lounge.
Gibbons went to sleep nearby on a couch.
About 8.30am the next day the victim woke to find Gibbons touching him. His pants and underwear had been removed and Gibbons appeared to be about to perform oral sex.
He pushed Gibbons away, shouting "f*** off" and then ran upstairs to find his friend.
From there he sent Gibbons a series of text messages about the incident.
Gibbons denied anything had happened.
Police charged Gibbons with indecent assault.
He also faced a second charge relating to an alleged indecent assault against another player at a tournament in Dunedin in 2016.
Gibbons pleaded not guilty to both charges.
After hearing all of the evidence a jury acquitted Gibbons on the 2016 charge but found him guilty of the 2017 charge.
Last month Judge Rob Ronayne sentenced him to six months' community detention, 18 months intensive supervision and 80 hours of community work.
The court heard that Gibbons still maintained his innocence and "does not acknowledge the conduct".
However, he accepted the jury's verdict and his conviction.
"He's not a predator," said his lawyer Ron Mansfield.
"Rehabilitation is crucial for him and the community… he will engage with any assistance he receives."
Judge Rob Ronayne said Gibbons had an "unfortunate" family background but had "risen above" that, gaining a sport scholarship to King's College and going on to obtain good jobs and start his tertiary education.
He went on to work at the school as a hockey and cricket coach.
Headmaster Simon Lamb did not return calls but said in a statement: "Mr Gibbons was not an employee of the College. He provided contracted services for sports coaching and his contract ceased in 2016 which was prior to my time as headmaster."
After Gibbons left King's he applied for a job as coach for Auckland Hockey.
David Curtis, the former chief executive of Auckland Hockey who employed Gibbons in April 2016, said he did he not know he was charged for indecently assaulting the player at a hockey tournament in Dunedin the same month he started his new role.
"I wasn't made aware of it at all. I had no knowledge. I am sitting here a little bit dumbfounded to be honest," Curtis said.
"I had no issues with Cameron as an employee, he was a very good coach and enthusiastic about the sport and keen to get kids and adults to play.
"He was a very competitive athlete which is what you expect from someone who plays at a high level. As a young man he certainly gave it his all."
Auckland Hockey chief executive Manoj Daji said he acted "swiftly" and conducted his own investigation into the indecent assault.
"It ended up being an employment matter and police brought charges within a week of us [investigating]," he said.
"It's my job to make sure the duty of care is upheld, that's my number one role. My actions were pretty swift and clear."
Daji said protocols were in place around alcohol within Auckland Hockey that were reinforced regularly.
"If they are on a tournament, they are under our duty of care, but when they are back and out of uniform it's up to the players."
At sentencing Judge Ronayne said Gibbons had worked hard and had potential, but he still needed to be held accountable for his sexual offending.
He said the assault was "intrusive" and there was a degree of planning and premeditation.
The victim was vulnerable as he was sleeping when the assault began, and because Gibbons knew how intoxicated he had been the night before.
"The act was not a mere touch… this was no impulsive act, there must have been some degree of deliberation on your part," he told Gibbons.
A pre-sentence report stated that due to Gibbons' denial of the offending he lacked insight, so there was a medium risk he would reoffend.
He was considered a high risk of harm to others due to the nature of the offending.
Judge Ronayne ordered Gibbons, as a condition of his supervision, to attend a psychological assessment and any counselling or programmes recommended as a result.
"The word here is help - not punishment," he said.
"Addressing whatever issues there are in your life that need addressing."
After sentencing Detective Senior Sergeant Megan Goldie said police were not aware of any further allegations against Gibbons.
