Perhaps it was the forearm to the face that made Sydney FC realise this was not a fight they were going to win.
In the 40th minute of the major A-League Women semifinal on Sunday night, Western United striker Hannah Keane received a pass near the touchline and, feeling Sydney defender Charlotte McLean closing in behind her, swung her arms wide as she tried to protect the ball and spin in-field.
But instead of simply bodying McLean off her back, the American's outstretched hand smacked into the centre-back's face as she turned, forcing McLean to tumble into the grass with a yelp of pain as she grabbed at her recently-fractured cheekbone.
Keane launched herself forward, taking a few determined strides before the referee's whistle ended the counter-attack that had sprung from this small but brutal moment.
Indeed, there were small but brutal moments unfolding all over the Sydney Football Stadium pitch as the two teams who finished first and second in the regular season battled it out across 90 minutes for an automatic spot in the ALW grand final on April 30.
Down the right, Western's stand-out young winger Kahli Johnson, who had left the newly-crowned premiers at the end of last season in search of more game-time, regularly found herself tussling and tumbling with Sydney full-back Kirsty Fenton, while veteran TJ Vlajnic twisted and turned Charlize Rule on the opposite side.
The Taranto twins fought and fouled Sydney's usually irrepressible midfield of Sarah Hunter and Mackenzie Hawkesby, full-backs Angela Beard and Stacey Papadopoulos stuck out arms and legs in an attempt to halt Matildas wingers Cortnee Vine and Princess Ibini, while central defensive pairing Sydney Cummings and Alana Cerne flattened Rachel Lowe and Madison Haley more often than not.
It was not a pretty game from Western United. It was not a game of finely-tuned tactics, scenes of individual brilliance, or choreographed passages of play; the kind of football that their much-favoured opponents tried (and often succeeded) to do. Knowing that they could not dominate Sydney FC in a footballing sense, Western instead set out to win it in a fighting one.
They knew it could work. After all, it was how they inflicted one of Sydney's four losses of the entire season back in early January, with two scrappy, opportunistic goals to Keane thanks to fortuitous deflections from desperate, clattering tackles.
Western United have never claimed to play good football. What they have done, though, is play effective football: the football that is necessary to get them where they want to go.
"It's evident in the way that we play: it's not scrappy, but it often gets results," head coach Mark Torcaso said in January. "Let's get results. Let's build foundations for our club.
"Obviously, the impact that we have in year one is very important for the future of any young female, especially in the western suburbs of Melbourne.
"We know we can play. We've got some fantastic individual players. But sometimes you've got to grind games out and get results.
"We're not the prettiest type of footballing team. But that's also because we're still establishing ourselves and the way we want to play."
The stats from Sunday night's game paint the picture of a team that forces themselves beyond the numbers. While Sydney dominated every category from shots (26 to 8) and possession (55 per cent to 45) to pass accuracy (68 per cent to 57) and corners (5 to one), it was the only number that really matters in the end — the score — where Western won the day.
That their first and only goal came through Keane, who crashed the ball home against the run of play, mere minutes before sending McLean tumbling into the grass, said everything about what this brand-new ALW club has been building over their inaugural season: a culture based on fighting harder and longer than everyone else.
It's a fight they're trying to win off the field, too.
As a club, Western United have struggled to imprint themselves in Melbourne's west. The lack of a home stadium — which had been promised in their original expansion bid — has made them nomads in their own state, wandering from place to place as they attempt to build a fanbase around them.
Despite the early success of their men's and women's teams, the community of fans continues to grow at a glacial pace; something that will likely become startlingly apparent at this season's grand final, which will be held in Sydney regardless of which team Western will end up facing there.
This season has also been a battle for Western's players and coaches to prove themselves: not just to the rest of the clubs in the league, but to the rest of the Australian game, that a team developed at the National Premier Leagues level — many of whom had never played professionally before — were capable of matching it with the best emerging talent in the country.
Sunday's final ten minutes epitomised all of that: as Sydney threw everything at their opponents, Western's bruised and battered players threw themselves right back at them, barricading themselves within their own penalty area as the Sky Blues tried to slip through any crack or crevice in that green-and-black wall.
Anchored from behind by the ALW's stand-out goalkeeper Hillary Beall, who saved every shot Sydney managed to put on target (12), pouncing and tumbling around in the sandy turf, Western muscled their way towards history.
It was gritty. It was ugly. It was rough and rugged and raw. But now, it has them into the grand final, becoming just the second expansion club to do so since the arrival of Melbourne City back in 2015.
Sometimes it's not about the dog in the fight, but the fight in the dog.
"I never thought we'd be in this position," Torcaso told Channel 10 after the game.
"We worked extremely hard in the off-season to get this team right and get this club right in regards to the [women's] space, so to be in this moment right now — now to be playing a grand final — is absolutely amazing.
"We didn't expect [Sydney] to have that many shots on target against us, but we defended well. We knew it was going to be a tough game; they've got probably the best front-line in the league. So for us, it was about sticking to our tasks ... and get a sucker-punch goal. And we got one and we just defended that.
"This season, every game that we've played, we literally fought for each other. Having people like Chloe [Logarzo] and Jess McDonald that helped drive those things are very important for our group.
"You saw it today: it was typical of our season. We just literally grinded out games and worked really hard for each other. It's a credit to the girls and to the club and everyone that has been part of this."
Western United will play the winner of Sydney FC and Melbourne Victory, who face off in next weekend's preliminary final.
