The Russian won the title nine years ago but this time around exited at the second-round juncture after a 6-3 6-4 loss to her unfancied Portuguese opponent.
Until now Larcher de Brito has been best known for her loud high-pitch screech, but on Wednesday she showed her on-court credentials by outplaying the four-time grand slam champion on Court Two.
Sharapova did not go down quietly, though.
The 26-year-old arguably edged the battle of the shriekers and may well have something to say about the surface after becoming the latest player to be hurt when slipping on the turf.
With few giving Larcher de Brito a chance on Wednesday, much of the build-up surrounded the potential noise level.
Larcher de Brito was once reportedly recorded screeching at 109 decibels - equivalent to the noise produced by a motorbike - while Sharapova is not known for being quiet herself.
The Russian had reached as high as 84 decibels by the time she was broken by the Portuguese in the fourth game.
Sharapova was looking rusty and only just managed to hold serve as Larcher de Brito threatened to go 5-1 up in the set.
The 20-year-old qualifier would not be denied for long, though, and took the first set in just 34 minutes to the astonishment of most in attendance.
Larcher de Brito continued strongly when play resumed, displaying an impressive array of shots that again saw her break the four-time grand slam champion in third game.
A double fault proved decisive for Sharapova, who went down particularly awkwardly midway through the set after slipping near the baseline.
It was not the first time the Russian had taken a tumble and led an irked spectator to shout "Sort the court out".
The trainer was called out by Sharapova and, while she was worked on courtside and then away from the public glare, there were audible gasps from the crowd as they saw the number of injuries in other matches on Wednesday.
Sharapova bravely returned despite what appeared to be a hip complaint but the match continued in the same vein.
Larcher de Brito held serve and, despite wasting a flurry of match points, secured a famous win, setting up a third-round tie with Italy's Karin Knapp.