The Giants' previous two matches against the Cats – in 2012 and last season – had resulted in close games to half-time, but ultimately defeats by 65 and 59 points respectively.
This time around, their improvement was clear for all to see when a 36-point deficit early in the final term was followed by a superb burst of football that allowed them to get within six points deep in the quarter.
The Cats were able to hang on and secure a 13.16 (94) to 12.15 (87) victory and afterwards, the feeling in the GWS rooms was one of undeniable disappointment.
"Yes it is," coach Leon Cameron said. "Disappointing that in the third quarter, they kicked six goals, when it was an even first half.
"We had opportunities in the second quarter to go a little bit further ahead, but coughed up that lead coming into half-time.
"But it's really pleasing on the other end, a six-day break coming back from Perth (in the loss to Fremantle), it was fantastic for our boys to understand they can push through games like that.
"To have 20 inside-50s in that fourth quarter and keep peppering the goals, that was the pleasing thing.
"But it's disappointing we lost the game. We're here to win games of footy.
"It was a good effort, but we're a little bit flat."
GWS co-captain Phil Davis was sharing the exact same sentiment.
"One of the most positive signs out of all of it was that we came in the rooms and there was a very, very big element of disappointment," he said.
"Early on in our time, people talked about honourable losses. I think we're past that stage.
"We want to be a football club that wins and wins all the time, and I think tonight sets a standard that we're starting to make some really big strides and we expect to perform to that level against every opposition."
The match provided a break out game of sorts for GWS' No.1 NAB AFL Draft pick Tom Boyd.
Playing in just his fourth game, Boyd was well held early, but nearly bobbed up as the match-winner in the final term.
Taking some key contested marks and slotting two goals, including a set shot from around 50m deep in the fourth quarter that brought the margin back to seven points, Boyd gave a glimpse of his enormous talent.
He doesn't turn 19 until next month, but the upside is undeniable for the 200cm, 104kg prospect.
"It was a tough night early," Cameron said when asked about Boyd's performance.
"He's up against (Jared) Rivers and (Harry) Taylor and (Tom) Lonergan, terrific backline players, and it was tough for Jon (Patton), Jeremy (Cameron) and Tom.
"But they're young kids, they're going to go up and down in games and go up and down from week to week.
"But we've just got to be patient and it was good for Tom to clunk a couple of marks in the last quarter that we know he can take, and to kick a couple of goals was really pleasing for his confidence."