The win ended the Breakers’ 16-match winning streak and extends the Cats’ streak at their home stadium to 13.
They will take on Wollongong at home on Thursday night in the best-of-three semi-finals series.
Coach Rob Beveridge said the game was all about finals preparation.
‘You could not come up against a better team when trying to prepare,’ Beveridge said.
‘We lost Damian Martin as a late withdrawal through injury, so for everybody, on late notice, to be able to step up was sensational.
‘It just shows on late notice somebody can get injured, but we know we have this belief that if somebody goes down, like a key player and captain in a Damo’