Ellis explained Sykes was being closely monitored to represent New Zealand, but would need to prove his worth during a yet-to-be announced fight in January.
He said there were two or three light heavyweights (under-82kg) currently in the mix, who could potentially represent the country at the Rio Olympic qualifiers in China in March.
However, only one fighter from each weight division can be sent to compete at those qualifiers.
Ellis said a trial event would likely be held in January to find the best fighter in each division.
During that event, Sykes will have to win his fight and show the selectors he is good enough to compete on the world stage.
"You need to show the selectors that you can win at the top level."
In the build-up to the January fight, Sykes will be sparring alongside Commonwealth Games gold medallist David Nyika (Hamilton), who is coached by Ellis.
Sykes, who has about 90 fights next to his name since he started boxing at the age of 12, said he was in the best condition of his life.
"Yea, I'm in the best shape I've been in," he said. "I'm trying to train as much as possible.
"I'm trying to get one more fight before Christmas and train up until that big fight in January."
He said he had considered going professional a couple of times, but had decided to remain an amateur to try to fight at the Olympic Games.
The 26-year-old, who is not one to talk himself up, said during the past two years he'd been taking boxing more seriously than ever before.
"I guess I had enough of partying and that type of thing and matured a bit, and thought I should start doing stuff with my life a bit more."
Sykes almost qualified for the Commonwealth Games last year but was beaten by Nyika in a qualifying fight.
Sykes is coached by his father Mike Sykes and trains out of their family gym, Sykes Boxing Gym on Tania Cres.
He said he enjoyed training and helping out with the juniors at the gym.
Three Olympic spots are up for grabs in the light heavyweight division during the Asia/Oceania Olympic qualifying event in China in March.