Newcastle were play-off spectators for the second consecutive season, and ultimately finished eighth, three points adrift of the top six, after leaving their run too late.

But the return of O'Donovan from Brisbane Roar mid-season, combined with the appointment of new coach Carl Robinson, sparked a form resurgence that delivered seven wins and three draws in the last 11 games of the season, including victories against eventual champions Sydney and runners-up Melbourne City.

"Had we got in there, we would have had a good chance of winning the competition, there's no doubt about that," O'Donovan said.

"Obviously a poor first half of the season cost us, but the style of football we were playing at the back end, I think we would have been a threat against any team. We showed that, because we were beating them.

"Hopefully we can keep most of this squad together and come back and be a force next season."

Nonetheless, O'Donovan said improvement was needed for Newcastle to feature in the sudden-death phase of their next campaign.

"Every team has to evolve and improve, or else they go backwards," he said.

"But certainly we've got a lot of energy, and a good balance of experience and youth, pace and strength.

"We've got good legs in the right places, which is a good sign moving forward."

The 35-year-old Irish import, who is in the process of becoming a naturalised Australian, admitted he would miss playing alongside Socceroo Dimi Petratos, who is bound for Saudi Arabian club Al Wahda.

"That's the hard part of football, is when good people leave to progress their careers elsewhere," O'Donovan said.

"Obviously it's sad for everyone that Dimi is moving on, but we wish him well. He's done well for Newcastle Jets and been a great teammate of mine.

"We've had a great partnership, scoring a lot of goals, assisting each other to score goals, and we've won a lot of games.

"But good to luck to him and his family. I hope it goes well for them."

With 49 goals in 103 games, O'Donovan is 14^th on the list of all-time A-League scorers and has his sights set on the half-century early next season.

"It would have been nice to get the 50^th before the end of the season, but that's one box I'll be keen to tick next season," he said.

"I look at the bigger picture. It would be nice to get in the A-League top 10 [goalscorers], top five. As a striker, scoring goals and helping the team win games is what it's all about ...

"I certainly don't think I've peaked in the A-League yet. I'm confident there are many goals to come, and hopefully there are more grand finals to come. That's my main goal."