Not far from the Olympic tennis centre stands one of this city's most iconic outcrops – Pedra da Gavea. It is a mountain that assumes a popular place in the mythology of the region.
In markings on one of its sides people see a human face; patterns on the other conjure to the eye some sort of inscription. Geologists and scientists insist the images are the result of simple erosion and not a message or gift left behind by previous civilizations.
In other words, the mythos of Pedra da Gavea is nothing more than a hope, a fantasy that doesn't exist in fact.
Which brings us to Eugenie Bouchard, who made her Olympic debut Saturday against American Sloane Stephens, a player with whom Ms. Bouchard has more than a passing acquaintance. The two have been playing against one another since the age of 12. Professionally, they had faced each other four times before this match, splitting the series 2-2.
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On Saturday, Bouchard took the lead, with a straight-set victory over her childhood rival.
It was a match that epitomized the best of Bouchard's game; a strong and deadly-accurate backhand; a forehand that moved her opponent around the court; and perhaps most of all a relentlessness that reminded spectators of the old Genie, the one who had many, including tennis legends like Chris Evert, suggesting she was made of major championship stuff. There were few signs of the shaky confidence, the aversion to pressure that has become a deadly albatross since her breakout year.
"I was trying to be very solid and I think I did that well," Bouchard said after the match. "I didn't give her many chances. I was happy that I was just mentally focused. I want to get every ball and turn defence into offence. And I think I did a good job of that today."
Like Pedra da Gavea, people see what they want in Bouchard. There have been many of late who have adopted the view she will never again regain the form that made her a threat in the majors two years ago. Her 2015 season was a much-chronicled wipeout, with her confessing after it was over that a dramatic weight loss was the result of an inability to eat because of pressure-induced nerves.
This season there have been some promising signs, if not ones that suggest she is ready to climb back into the major championship conversation, at least ones that indicate there is still a tonne of talent inside that 5'10' frame, even if she has insisted on only allowing it out sporadically.
During the match, there was none of the defeatism that Bouchard can sometimes demonstrate; the slumped shoulders; the on-court racquet smashing; the looks of disgust up at the skies. This time it was Sloane who adopted many of those poses.
The win is only that, one win, but it was against a higher-ranked player (the American is ranked 22 currently, Bouchard 39th) so it was not an insignificant accomplishment. If Bouchard had lost there would have been many who questioned her decision to march with the Canadian team in the opening ceremonies the previous night, which kept her up late. She didn't question that move for a second.
"I wouldn't have missed it for the world," she said after her match. "It's a moment I'll remember for the rest of my life. If anything it gave me extra motivation today."
It was nice to see Bouchard in such fine form. Some will suggest it's a mirage, a beautiful demonstration of her sport that she can't pull off regularly anymore. That as soon as she runs into an aggressive opponent who keeps the pressure up on her she will fail. That opponent could well be her next one, who most expect will be the German Angelique Kerber, ranked second in the world.
If that collision does occur we could be having a completely different discussion next week depending on how she performs, depending on whether she allows the mind to wander, her confidence to wilt in the Brazilian heat.
Bouchard looked good wearing Canada's colours. She seemed to get a lift from the red and white (and black). After the match was over she looked happier and more content than she has in a long time.
"I'm a cloud right now," she said. "I'm going to sleep well."