Australia's recent dominance over their South American rivals continued on Tuesday night with a 3-2 friendly win in front of a huge crowd in Newcastle.
Along with those 17,000 fans, the world watched on TV as Kerr netted a double and set up a third to wrap up the two-game friendly series following Saturday's 2-1 result in Penrith.
Their visitors' displeasure was obvious in a spiteful final 15 minutes that involved some push and shove and then the spurning of post-match sportsmanship.
The animosity heightened when Marta felled Caitlin Foord, before the Brazil star drew a questionable penalty off Ellie Carpenter and converted from the spot.
After the full-time whistle, Matildas players could be seen attempting to reach out and shake their opponents' hands only to be snubbed.
"Not shaking hands," said Kerr, "it's not an Australian thing but I'm not really going to comment on it because it's not something I think is very ... I don't really like it, but whatever.
"It was heated. I don't know how it started. I just saw Caitlin fall to the ground, but I guess that's what happens when you get under people's skin, not only in the game but the last three matches.
"It was disappointing to see. We think of them as a very highly respectable team and I don't think we got the respect we deserved tonight after the last three performances."
Kerr's dazzling performance - including a trademark poacher's header - further cemented the shortlisted 24-year-old's case be named FIFA world player of the year.
Ever-grounded, she re-directed praise to Emily van Egmond's superb assist.
"We've been working on those ones," Kerr said.
"In the game in Penrith one nearly came off too and it was cleared off the line.
"It's no fluke - Emily always puts in great balls and everyone just has to get on the end of it. "