Tackle-busting second rower Liam Wiscombe produced a 25 metre run through the Tigers' defence to reduce the margin to two points before Jenkinson showed tremendous composure to slot the goal from 10 metres to the left of the posts for a 28-all result.

"It was a really good effort and there's plenty of promising signs," delighted coach Adrian Purtell said.

"The effort that everyone was willing to put in for each other was something that you can really build on.

"Hopefully it stands us in good stead for a successful season."

The Thunder had a heartbreaking run of close losses last season, falling by 10 points or less in eight games.

Former NRL player Purtell will be hoping the gritty comeback is a positive sign and last year was just bad luck.

The Tigers stunned the visitors, racing to a 12-nil lead after only nine minutes.

The Thunder steadied through winger Ty Tindalevale before Luke Ingram scored two tries in five minutes to hand the visitors a shock four-point lead at half-time.

And the underdogs extended the margin when Sabastian Rapana crossed at the 17-minute mark of the second half, Jenkinson's conversion pushing the lead to 10 points.

But Gundagai launched a 14-minute blitz, scoring three tries to grab a 28-22 lead with seven minutes left.

It looked like deja vu for the Thunder from last year until Wiscombe's barnstorming effort and Jenkinson's coolness.

The only negative was a potential broken jaw to centre Damian Scott, with officials hoping for some good news on that injury front.

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