The Sharks have made it six wins on the trot in the Holden Cup with a gritty 28-20 victory over a Melbourne side that included Junior Kangaroos Brodie Croft and Curtis Scott.
Back-to-back penalties put the Sharks straight on the attack and they didn't disappoint with in-form centre Bessie Aufaga-Toomaga racing through to ground a grubber after six minutes.
It didn't take long for the Thunderbolts to hit back with late inclusion Scott Drinkwater powering his way over from close range before teammate Brodie Croft dummied and stepped past the defence to give the visitors a 10-6 lead.
Unaccustomed to chasing points at their home ground, Cronulla quickly regained the ascendency when some slick passing in tight traffic finished up with Kyle Flanagan diving over to make it 12-10 after 28 minutes.
The hosts moved further in front three minutes into the second half when bustling back-rower Tony Matautia made light work of three would-be defenders to give his side an eight-point cushion.
A slip in the defensive line allowed Drinkwater to waltz over for his second of the evening to cut the gap to two points before the fill-in fullback charged onto a perfectly-timed short pass from halfback Matt Egan to give Melbourne the lead.
The see-sawing affair continued with the Sharks reclaiming the lead 15 minutes from the end when lock forward Billy Magoulias crashed through Melbourne's defensive wall to make it 24-20.
The Sharks finally put the result beyond doubt when Briton Nikora took full advantage of some Blayke Brailey magic around the ruck to crash over for the match-winning try three minutes from the death.
Sharks 28 (Bessie Aufaga-Toomaga, Kyle Flanagan, Tony Matautia, Billy Magoulias, Briton Nikora tries; Kyle Flanagan 4 goals) def. Storm 20 (Scott Drinkwater 3, Brodie Croft tries; Scott Drinkwater 2 goals) in Holden Cup at Southern Cross Group Stadium. Half-time: 12-10.