I shocked the patriotic black cat on my lap (leaving him ashen-faced) by barracking for America's Alison Riske against our Ash Barty in the athletes' fourth round Ladies Singles match at Wimbledon.
"Most of the time you pretend to be a proud Australian but I think your patriotism is but a mere veneer," the astute companion brute accused as the match unfolded.
Back to sport and patriotism and Our Ash in a few moments, but first, still on women and sport, let me rejoice at my loss of my prejudice against women's football (soccer).
Following the 2019 FIFA Women's World Cup has been a revelation.
A lifelong follower of men's football (I go to local matches every weekend and am even wearing items of English Premier League Norwich City FC official merchandise as I write this and have an official merchandise Norwich City garden gnome on my rockery) I have been glacially slow to appreciate and embrace the women's game.
An average player myself in my heyday (that heyday now lost in the mists of time) I have done a lot of sexist scoffing at women's football.
The causes of my conversion are of no matter because my bigger point is how good it feels to shed a big, fat prejudice.
One feels somehow intellectually lighter, more cerebrally nimble, just as if one had lost a great blob of hampering flab.
What could be next, one wonders, marvelling at what has happened?
What of my lifelong loathing of the Liberal Party and my contempt for its rat-like voters? What of my 50 years of atheism? What of my lifelong certainty that astrology is crap?
Quite apart from my fear that Ash is in danger of being made a toweringly tall poppy by Australians irrationally inclined to worship her, there were some very engaging things about Ms Riske.
What if I have only felt that way because, like all Sagittarians, I have an irrational preoccupation with the so-called "truths" of scientific evidence?
Meanwhile, back on my couch, as well as barracking for Ms Riske I called out lots of tactical tips to her. Gratefully adopting them, she battled her way to a 3-6, 6-2, 6-3 victory.
At her post-match press conference she was probably on the verge of thanking me by name, when, instead, overwhelmed by joy, speech gave way to tears.
The cat, colour (pitch black) now returning to his face, continued to demand to know why I hadn't barracked for Our Ash. I explained to him that quite apart from my fear that Ash is in danger of being made a toweringly tall poppy by Australians irrationally inclined to worship her (more of this theme in a moment) there were some very engaging things about Ms Riske.
So for example while Ash's stroke-making and athleticism are so elegant (her tennis game is sometimes poetically described as "silken") Riske's game is engagingly untidy and odd and wild-looking (Ash runs like a gazelle but Riske runs like a Staffy terrier), and reminds lots of us of our own tennis style, or lack thereof. If Ash's tennis is silken then Riske's is engagingly, humanly hempen.
Then, too, I have always approved of tennis players, male and especially female, who make lots of vocalising noises while they play. Ash is eerily, robotically quiet. Riske vocalises on almost every shot, sometimes a gasp of exertion, sometimes the yowl of a war-cry, often a blend of both.
It is not only that athletes truly exerting themselves and truly showing combative determination should be making noises but also that women athletes in particular must be free to be seen and heard.
Sexist fogeys who complain about the noises female tennis players make never make the same complaints about the often far louder noises (often windowpane-rattling, bull-like bellows) made by male players. This is because they, the fogeys, cling to the idea that women, even when they are playing sport, have a duty to be decoratively girly, to be seen and not heard.
The engaging noisiness of some female tennis players somehow reminds me of what it was that those of us old enough to remember used to love about steam-powered railway engines. Their hissings and whooshings and clankings told us that they were living things, like those of us who admired them.
The diesel and then, worse still, the whispering electric engines that took over from them lack flesh-and-blood mechanical charisma.
So give me, at the tennis, men and women who are cacophonously steam-powered.
Ms Riske, as I barracked for her, was entertainingly and engagingly a creature of steam. I identified with her as a member of my own gasping, puffing, clanking species.
Then, too, I was not looking forward the national gushing that would have followed Ash's winning of the Wimbledon title.
Already, everywhere one eavesdrops on the national conversation one hears Ash being talked about with an awed, sentimental reverence. Her deification, what we might call her MacKillopisation (for her secular canonisation is irreversibly underway) seems to me rather unAustralian.
Perhaps it is perverse of me (I do hope it is) but I am far more comfortable with flawed national sports stars like Nick Kyrgios than with flawless, MacKillopesque ones like Our Ash.
I look forward wistfully (for one doubts it will ever happen) to the day when on court Ash does something refreshingly, uncorkedly Kyrgioesque, perhaps a little exhilarating racquet abuse, the throwing of a revivifying tantrum laced with f-bombs.
"But that would be unladylike!" I hear the fogeys, for whom feminism has never happened, gasp into their cocoa.