Ben Linde's SG Ball side led minor premiers Manly 18-10 at the break but trailed 23-22 with just eight minutes left on the back of a field goal to Eagles half Jamie Lawler.

Having claimed the prelim final by four points with a 68^th minute try in the prelim final a week earlier, the Steelers produced another clutch effort, Talatau Amone crossing for the go ahead try five minutes from time.

With the game still in the balance, Treigh Stewart sealed the deal in the 69^th minute to ensure the trophy headed south to Wollongong.

Halfback Jayden Sullivan proved the key man, grabbing two tries, having a hand in two others and kicking five goals in a commanding display in the No. 7 jumper.

"We just play with eyes up, we don't guess, we all know each other," Sullivan told NSWRL.

"We had a rough start to the season but to come out on top is just amazing. I'm absolutely amazed.

"Without these boys I'd be nothing. Just because I'm captain doesn't mean I'm above anybody, we're just one team."

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Earlier on, Daniel Lacey's Tarsha Gale Cup side etched their name on the famous trophy with a 24-12 win over Newcastle in the first match of the day at the new stadium.

The Steelers led 10-0 after just five minutes with an early try to Olivia Vale and an incredible 70-metre solo effort from Teaghan Berry.

It wouldn't be the try of the match however, with Tiana Graham producing one of the great grand final tries 10 minutes into the second period, beating five defenders in a Steve Jackson-esque run after grabbing an offload from skipper Maddie Weatherall.

Graham made another jinking run to put Mikayla Kidd over for the match-winner after Berry grabbed her second try of the afternoon.

Having watched the 16-year-old make the move from Western Australia to chase a league dream, Lacey said he couldn't be prouder.

"Tiana's a year young, she's come over from Western Australia and her mum's moved with her," Lacey said.

"They've made a commitment to rugby league so I've made a commitment to her.

"I needed to tell her what she was good at because I don't think she realises how good she is. I just said 'for us to win we need you to run'.

"She's a good ball player so she likes to feed the outside backs. I thought her first few runs were a bit pre-line and a bit slow so I just said 'look, you've just got to go' and didn't she what."

It was a validating win for the Steelers, who've been pace-setters since the competition began only to fall at the semi-final stage in previous seasons.

"As a coach you normally get a good vibe of how your team's going but you don't want to let it out externally, you just want to bottle it up and make sure they're on point," Lacey said.

"I knew there was a good vibe about this team and what we've built previously. We added to the squad and the way we trained... the full package came to fruition.

"You can't just have a couple of good players, you need a whole group to get you there The fight they had in them, you'd have thought they were 10 down not 10 up. They just didn't want to let them score.

"It's where we fell short against them earlier in the year. It's testament to how they've listened and learned through the year and how they've applied themselves whether the chips were up or down. They deserve it."