Novak Djokovic - the number 1 tennis player in the world - has spent the sport's hiatus endorsing a product that claims to stimulate brain cell growth.
Celebrities from all walks of life have used social media to connect with their fans.
Neil Young has plundered his back catalogue by a campfire, while European Ryder Cup captain Padraig Harrington has been offering golf tips from his back garden.
Novak Djokovic has been giving a platform on his Instagram to someone called Chervin Jafarieh and his unique brand of snake oil.
Among their many theories is that emotions can alter the molecular structure of water.
Sure, there have been one-on-one conversations with Andy Murray and Maria Sharapova, but neither of those claim they can enhance "mind-body connection" for $50 every 60ml.
In his latest Instagram Live video, Djokovic spends over an hour speaking with Jafarieh about "the natural detoxification process of the body and why is it so essential that we start our day in the right way".
At the time of writing, the video has racked up 579,674 views.
Not approved by the FDA
Jafarieh is the man behind Cymbiotika - a company that sells non-GMO and vegan potions which have been "Isolated from the pristine coastal waters at the Bay of Fundy in Nova Scotia, our Pure algae strain offers the highest level of omega-3 DHA without compromising nature’s perfect formulation."
They have not been approved by the American Food & Drug Administration (FDA).
Jafarieh is a former real-estate broker, but then "wanted to be a benevolent king who took care of everyone."
Many of his products are for sale using a recurring price, while certain bundles go for as much as $224 (€206).
Djokovic has already courted controversy during the lockdown, saying he'd refuse a coronavirus vaccine if one were to facilitate a return to normality for the world of tennis.
World no.2 Rafa Nadal has volleyed back, saying "Djokovic will have to be vaccinated", if that's the route the International Tennis Federation want to head down.
He's espoused the virtues of meditation, and the 17-time Grand Slam winner put his upturn in form some years back to switching to a vegan diet.
Turning toxic water into pure
While Djokovic spoke with Jafarieh online last month about the mental impact of the COVID-19 shutdown, Jafarieh warned: "Your immune system will suffer because you're under the state of fear."
In their latest tete-a-tete they claim that proper connection when drinking water - of any quality - can change its molecular composition.
The Serb does stipulate that: "This is something that is not linked to any form of official way of presenting nutrition and how you should eat and drink."
However, Djokovic goes on to put forward the notion that, "I know some people that, through energetical (sic) transformation, through the power of prayer, through the power of gratitude, they managed to turn the most toxic food, or maybe most polluted water into the most healing water, because water reacts.
"Scientists have proven that in experiment, that molecules in the water react to our emotions to what has been said."
That theory came from Japanese author Masaru Emoto - who is not a scientist.
Jafarieh also claims - in the same video - that by manipulating your body and bending in different ways you are helping to squeeze toxins out of the body.
Djokovic takes notes too when told that putting your feet up, or using a trampoline, are "important ways of detoxification."
Somehow, you kind of expect better of the world's best tennis player.
Experienced tennis journalist Jon Wertheim certainly does. He told the Tennis Channel, "At a time of coronavirus, when false stories and conspiracy theories, bleach consumption and UV rays are being legitimised, I think he really needs to be careful.
Wertheim added, "There are consequences from this. I was disappointed to see that. There’s a real responsibility that comes from being No. 1 and part of that comes with respecting science and objective truth."