The result was even more significant given the circumstances, as the Warriors' preparation for the match was severely disrupted after their flight was diverted to Brisbane on Friday night, due to an electrical storm in Sydney.
It meant they only had five hours sleep, before boarding an early morning domestic flight to Sydney on Saturday.
Captain Laura Mariu was a standout for the Warriors, while fullback Apii Nicholls, lock Louisa Gago and hooker Krystal Rota were also impressive.
Wing Hilda Mariu grabbed a slice of history for the Warriors in the NRLW opener when she crossed in the eighth minute, and like Phil Blake back in 1995, her name will always have a place on the club honours board.
The Warriors completely dominated the first 20 minutes. They monopolized possession, continually dented the Roosters defensive line and generally organised their sets well.
It was no surprise when they extended their lead in the 17th minute, after a period of sustained pressure. The visitors stretched the Roosters from east to west after consecutive penalties, before Louisa Gago ran a great line off a precise Laura Mariu pass.
However, the Roosters came back into the match in the last 10 minutes of the half, off the back of some cheap penalties and a couple of Warriors errors. The pressure told three minutes before halftime, when Isabelle Kelly crossed after a weaving run across field.
It was a shame for the Warriors, as the halftime scoreline didn't reflect their dominance.
The second half was more of an even contest, though the Warriors always looked more likely.
But they struggled to finish their sets well, and their persistent tactic of kicking on the fourth tackle didn't really pay off.
They had chances to put the foot on the throat, but couldn't quite do it, but defence and pure desire were enough to ensure a famous victory.
Warriors 10 (H Mariu, L. Gago tries; A Nicholls conversion)
Roosters 4 (I Kelly try)
Halftime 10-4
