Thwaites sunk a two-point shot with just under three minutes left to give the Vixens the lead in a final term full of momentum swings.
Emily Mannix won a crucial rebound in that final term too, fighting to the last despite having the unenviable task of containing Jhaniele Fowler.
“Holy crap, that was right down to the wire,” Thwaites said. “I just had such faith that we played out all of those scenarios. We knew exactly what to do. I’m just so proud to be part of this club.
“We really hope that you guys back home, [that] we have brought some light to you guys. We know that it has been really, really hard for you and we can’t wait to get home and just give you all a huge big hug.”
Vixens coach Simone McKinnis, who was reduced to tears in a pre-match video package talking about Victoria’s pandemic lockdown, said she felt “exhilarated” following the win, which came after 93 days in a Queensland hub.
“We said had right back at the start if they start talking about, ‘it is not a full-on season’, it was one of the toughest seasons in every way possible and I knew that we wanted to be the toughest competitors in this competition.
“So it was tough and it is huge. The team that was going to come out on top and win this it was going to be a huge effort.”
The first quarter was tight and enthralling but the real fireworks began in the second term.
Melbourne took the lead through a quick couple of goals to Thwaites but the Fever got it back quickly.
Then Kate Eddy, first up after injury, flew through the air to take a brilliant intercept that created another Vixens goal and gave her team the lead.
Player of the match Mwai Kumwenda defied the laws of physics to take a pass close to goal simultaneously on one leg and bending low to the ground.
Her battle with Courtney Bruce was intense, the Fever defender trying to snatch the ball off the Vixens shooter even after she’d scored.
Fowler was, as always, the ultimate target under the goal for the Fever, with Vixens Mannix and Jo Weston flying around her trying to blunt her influence.
Moments after Thwaites had missed a two-point shot at the other end Fowler sunk a Super Shot after the half-time buzzer to give the Fever the lead at half-time.
Where Fowler is big enough to stand and deliver, her opposite number Kumwenda was a constant dynamic presence for the Vixens. She scored using that guile late in the third term to give her side the biggest lead of the game at 47-42.
That lead was cut to three at the final change and the Fever got ahead of the Vixens early in the final term.
However the Vixens held their nerve and pulled off crucial intercepts and attacking plays to win the match.
Fever continue to look for their first grand final win after also losing in 2018.
“We have given up so much to be here. We kept growing this year. 2020 threw us lots of highs and lots of lows but I’m proud of all the effort we have put in and how far we have come. Bring on 2021,” Fever’s captain Bruce said.
Anthony is a sports reporter at The Age.