The Matildas earned a 0-0 draw with Sweden on Wednesday in what was a much-improved performance at the Guldfageln Arena.
After defeats to Germany, Netherlands and Denmark respectively, Gustavsson made an array of changes in an attempt to strengthen a defence that had shipped 13 goals since his arrival.
Among them was a switch to a 3-4-3 formation, with full-backs Steph Catley and Ellie Carpenter moving inside to partner Clare Polkinghorne in the first third.
Wing-backs Tameka Butt and Hayley Raso dropped deep to form a back five in transition against the Swedes and, while effective, it's unclear if Gustavsson will persist with such a system ahead of the Olympics.
"My thoughts are mixed to be honest," Gustavsson said after the game.
"I think there's parts of it that is solid, especially defensively. Sweden is a really, really good attacking team, especially on counters.
"I don't think we were as intense and aggressive and attack-minded as we have been in previous games."
Despite the attacking intent displayed in the aforementioned defeats, Wednesday's draw was perhaps Sam Kerr's best outing under Gustavsson thus far.
Kerr cracked the crossbar midway through the second half in what was her best chance of the game - one cut short after sustaining an apparent leg injury.
The 27-year-old's status will be monitored closely in the coming weeks, with her recovery crucial if the Matildas are to contend for a medal.
Australia will face Sweden once again in Tokyo, where they will look to progress out of a group containing world champions USA and fellow 2023 FIFA Women's World Cup hosts, New Zealand.
The anticipated rematch is one Raso is particularly keen on - even if the Matildas are still a "work in progress".
"For us it was nice to go out there and get a clean sheet," Raso said.
"We showed our fighting spirit today and that is the belief we need going into the Olympics.
"It's a work in progress for us but that definitely does give us the confidence that we need."
Gustavsson now has a little more than a month to mull over his preferred personnel for the Games, knowing full well the critics won't keep quiet for much longer if a maiden victory isn't forthcoming.
