The 22 year-old looked like he wouldn't be able to return to the field after copping a heavy knock in the first term, but he proved the difference in the dying minutes.
With the Hawks looking like they were going to bridge the gap, Ross booted two steadying goals and set up another to help send his side into a Semi Final battle with Casey.
Ben McKinley was another important player throughout the day with three goals from his 15 disposals, and he had plenty of assistance in attack from Ben Warren in a game that didn't suit the forwards.
Warren had 16 possessions and kicked two majors, while development coach John Lamont was also pleased with the effort of Gavin Urquhart who had 12 touches and worked hard with and without the ball.
Cameron Pedersen would have been disappointed to be omitted from the senior side, but he handled his role in defence with aplomb, and Majak Daw was also impressive in the ruck racking up 27 hit-outs and nine marks.
Without Aaron Black, Ben Cunnington, Shaun Atley and Daniel Pratt all playing AFL, reigning premier North Ballarat was never in the hunt against a rampant Seagulls' outfit and had a 67-point loss.
Brayden Norris and Marcus White were the only North Melbourne listed players in action, with the latter named among the best in a stopping role on the dangerous Andrew Hooper.
White also had 16 possessions of his own, while Norris ran hard on the wing and defensively with four tackles to go with his 16 disposals.
It's do-or-die for both teams this week as the Tigers face the Casey Scorpions on Saturday and the Roosters come up against last year's Grand Final opponent the Northern Bullants.
Werribee Tigers 3.1 5.5 8.8 13.11 (89)
Box Hill Hawks 1.2 3.3 5.6 9.9 (63)
GOALS:
Werribee Tigers: McKinley 3 Castello 3 Ross 2 Warren 2 Prismall Tighe Chisholm
Box Hill Hawks: Ralph 3 Kiel Neil Pattison Wanganeen Mirra Jackson
BEST:
Werribee Tigers: O'Dwyer Chisholm Hartigan Castello Tuck Ruggles
Box Hill Hawks: Jackson Boumann Ralph Mirra Sierakowski Williams
Williamstown 2.3 8.5 14.10 20.14 (134)
North Ballarat 1.4 3.5 7.6 10.7 (67)
GOALS:
Williamstown: Panos 5 Hahn 3 Gilbee 2 Hooper 2 Hill 2 Skinner 2 Stretton Djerrkura Carr Howard
North Ballarat: Driscoll 2 George 2 Micallef 2 Tyler Dare Lynch Hoy
BEST:
Williamstown: Jolley Gilbee Panos Djerrkura Minson Hill
North Ballarat: George Tate White Hoy Micallef Sharke
