The veteran took his time to find his feet, but is now a key part of a disciplined Wanderers outfit marching up the A-League table
The classy midfielder had his best game for the Wanderers on Saturday as the competition newcomers outclassed local rivals Sydney FC 2-0 at Allianz Stadium.
While fellow big-name marquee stars Alessandro Del Piero and Emile Heskey started the season in sensational form only to fall away in recent weeks, Ono has shown improvement with every game.
And the 32-year-old admits after taking a little bit of time to settle in his new surrounds, he has no doubt his best is yet to come.
"I'm getting happier every week with how I am playing and my confidence is getting better too," Ono told Sportal.
"When I first [arrived] it was a bit hard but my fitness is getting better all the time.
"I appreciate the coach [Tony Popovic] has put support in me and has given me a chance and I want to do my best for him and [the] team.
"I'm happy [with my form] but I know I can do better with every game. I'm working hard with the team every day to improve."
Ono, who signed a rich one-year deal with the Wanderers at the start of the season, has an option for a second year and is hopeful he can extend his stay in Sydney's west.
"I don't know what is happening yet but I want to stay," Ono said.
"We still have to speak about it [next season]. I'm very happy with everything, the team is great and I want to play with them.
"I want to stay here."
Those words are just what Wanderers goalkeeper Ante Covic wants to hear, with the veteran shot-stopper crediting Ono's upsurge in form for his side's rise to fourth on the A-League table.
Covic believes Ono could be an crucial factor for the Wanderers toward the end of the season and is confident the former Japanese international will make a bigger impact on the league than Del Piero and Heskey.
"In the beginning he showed glimpses of being a fantastic player but he's just been improving week in, week out," Covic said.
"Come the end of the season I think he's going to be the star of the league and one of the best imports.
"On the weekend he controlled the game beautifully and some of his touches were amazing.
"We're reaping the benefits right now and that's only after 11 games... there's a long way left and a lot more out of Shinji yet."
The Wanderers will be aiming to win three games in succession for the first time in their history when they host high-flying Adelaide at Parramatta Stadium on Friday.