And for winners Wollongong United - it was a combination of part brilliance, part luck.

Kawasakaya Hikaru's low, powerful strike - which deflected off a Sharks defender and into the back of the net on the stroke of half time - would prove the match winner at Ian McLennan Park.

It was the momentum changer and, despite Woonona's best efforts, there was no way back in the second half. For the third time this season, United trumped the Sharks 1-0, and it was an arm wrestle to decide this year's premiers.

The result means that United's IPL side will finish the year winning three of the four pieces of silverware on offer. The only missing piece of the jigsaw was the premiers trophy, which the Sharks claimed last month.

On Sunday, a relieved United captain Danny Lazarevski told the Mercury it felt "absolutely awesome" to claim the premiership.

"I think It was well deserved for the boys after narrowly missing out on the league title. It just made us more hungrier for the grand final," he said.

"I thought we grinded it out really well. Unfortunately we couldn't get the sealer for 2-0, but once again we got that clean sheet which took us to the title.

"Three trophies for the club, it's fantastic. I think the club will be very happy with that and we're also happy with that too. Obviously it's been a strange year, being stop, stop and start. But there was still a competition there to be played and everyone was out there to win it, and we got out there for the win."

United coach Oli Vrtkovski said Sunday's win was a "consolation for not finishing first".

"You can see, just by the celebrations, to get the major for us is a great achievement," he said.

"We had a good couple of chances in the first few minutes, and then Woonona got on top of us. Then to grab one, fortunately for us off a deflection, was huge. But a goal's a goal, we'll take it. Half time was about keeping the energy high, the motivation was there. And you know what? The boys stood tall and didn't allow Woonona to create a chance in the second half.

"We had some standout performances in defence. There was great leadership from the group, particularly Danny 'Laz', Benny Brooks and Billy Tsolovos. They were fantastic defensively and they're the players that win you games."

Conversely, Woonona's Tyler Bromham-Fuller was left to lament a missed opportunity to get the premiership double. However, the captain was proud of his team's effort on Sunday.

"That's the trademark Woonona I guess. We never give up, we fight for everything until the end. But United have been a quality side all year and that was no different today," Bromham-Fuller said.

"That goal was the last kick of the half I think, and I gave away the foul there too so it hurts a bit more for me. But it was a quality finish. In big games, you need big moments. And they got them today."

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Woonona had the first meaningful attack of Sunday's game, with a long-range shot from Tomohiro Ishi forcing United goalkeeper Jordan Nikolovski to tap the ball over the cross bar.

United's first chance in the 15^th minute. From a free kick, Andre Dias put in a dangerous cross, which deflected off a defender into Kawakasakaya Hikaru. But his deft shot was just wide of the goals.

Minutes later, Mason Versi was able to beat Sharks gloveman Jair Fernandez, but his cross just missed Jeremy Flanagan's boot.

The scoring opportunities began to dry up after that moment and it became a contested battle, particularly between the teams' midfields.

With around five minutes left until the break, United captain Danny Lazarevski and Hikaru had golden opportunities in quick succession, but their headers were just off target.

On the brink of half time, Hikaru was dragged down outside the box, leading to Tyler Bromham-Fuller receiving a yellow card. From the free kick, Hikaru was able to slot it between the defenders and past a diving Fernandez to score United's opening goal.

The score remained 1-0 at the break.

United would bring that momentum swing into the second half, with Versi taking a lovely strike within the box. However, Fernandez was able to make an athletic save and deflect the ball away.

Around the 50-minute mark, United looked likely to double their advantage when Jeremy Flanagan found himself one-on-one with Fernandez, but the gloveman was up to the task.

With a 1-0 lead, United continued to press hard for more goals - and the only thing stopping them was Fernandez. Approaching the hour-mark, Hikaru looked like he had breached the goalie's defence for a second time, but his exuberant header just slid past the post.

At the other end, Nikolovski was proving equally impressive, flying high to take some impressive saves.

The game started to open up as the clock ticked down, with both teams playing end-to-end football.

Despite some half chances for both teams in the last 15 minutes, United were able to clinch the premiership with the 1-0 win.

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Earlier on Sunday, Wollongong Olympic claimed the IPL Second Grade premiership following a thrilling penalty shootout win over rivals Wollongong United.

The score remained at 1-all at full time, and then again after extra time. The game went to a shootout, where Olympic prevailed 5-3 to clinch this year's title.