Thornton and Kurri Weston will be looking to take a huge step in breaking extended premiership droughts when they meet in the Maitland first grade cricket semi-finals at Robins Oval on the weekend.
The Thunder last won the title 12 years ago and returned to semi-finals last year for the first time since winning that title.
While they won titles as separate clubs, Kurri Weston have yet to break the duck since merging eight years ago.
On the other side of the draw are two of the most successful sides of the past decade in City United and Northern Suburbs, who meet at Lorn Park on the weekend.
Norths have played in 10 of the past 11 grand finals, last winning in 2014-15 when they completed back-to-back title wins against City.
City have featured in four of the past five grand finals defeating Northern Suburbs in 2016-17 after losing to Wests in 2015-16.
City, Kurri Weston and Thornton finished on 56 points in that order after a rain-affected final round prevented Thornton from mounting a runs chase against City.
"It was a bit unfortunate to finish the season like that, but it's not the first time the rain has got it like that," Thornton skipper Jake Moore said.
"This year, in comparison with last year, we felt we had been a lot more dominant and it was a bit disappointing to finish in the same spot on the ladder
"Kurri Weston got their points on the first day to get through ahead of us and credit to them. It would have been nice to get the minor premiership, but it is what it is."
The forecast is not good for Thornton with rain threatening on Saturday and Sunday and a draw meaning Kurri Weston will go through to the grand final as the higher finishing team.
"Hopefully the forecast is wrong," Moore said. "We're all pretty excited about getting a shot to get the big one home.
"Last year, was the first time Thornton had made the semis since winning it 11 years before. It's 12 years ago since won it."
Hopefully the forecast is wrong. We're all pretty excited about getting a shot to get the big one home.Thornton captain Jake Moore
Moore said the major improvement for the side had been in their batting.
"The last few years our bowling has been strong. The difference this year is that we have just batted a lot better," he said.
"Over the past few years we've been able to restrict teams, there haven't been that many big totals over 200 against us. What's come of the low totals this year is we've started to chase a lot better than we had and got the results.
"I dont think we've got the best team on paper but as a unit we're a confident, young side and we back each other's ability to get the job done.
"I think that goes a long way in this comp.
"When we played Norths in the recent Saturday, Sunday round. At the back end of the game and Norths were cruising six down and only need about 40 runs.
"We took one wicket, got a sniff and ended up winning the game by 10 or so runs.
"No matter what we play it until the end. No matter how bad or how good we're still in it until the last ball.
"Kurri Weston have got very dangerous players in the top order, but once again we've just got to back our bowlers, set good fields and back our ability to take their wickets early or at least control their scoring areas."