Argentina and Uruguay have helped stoke up the excitement at this World Cup but it's the calming effects of mate which may be their lasting gift to the tournament.
Aficionados like Lionel Messi and Luis Suárez have been helping to spread mate's popularity among their peers, and players like France's Antoine Griezmann and England's Eric Dier have caught the bug.
Half a world away in Montevideo, the publicity the drink is getting from the World Cup is a boon to Federico Bresciani.
His family business, Bresciani Plateria Criolla, produces the highly worked leather gourds – in which the powdery yerba mate tea is mixed with hot water and imbibed – and has clients in 16 countries, including some of the world's greatest footballers.
And there's nowhere better to spread the word than at Russia-2018, where Uruguay have brought 180 kilos of the tea and Argentina, who took 200 kilos.
In his modest workshop seven craftsmen turn out these containers – gourds that are also called mates – polishing and finishing the edges with inlaid gold or silver.
A common sight in Argentina and Uruguay are men and women walking around with their gourds, sipping mate through a metal straw called a bombilla, a refill thermos flask of water tucked under their arm. An average drinker can consume two litres a day.
The stars of Uruguay's national team Luis Suárez and Edinson Cavani, Argentine captain Messi and midfielder Ángel di María, are regularly pictured with mate paraphernalia. The flask pressed between arm and midriff, the mate in hand.
Stars new to the mate scene are French striker Antoine Griezmann. Like the others, he's a client of Bresciani's.
More recently, English midfielder Eric Dier told the Daily Telegraph he was "slightly addicted" to the drink. His Tottenham Hotspur teammate, the Korean Son Heung-Min, shared a photo on social media of him sipping a mate recently. Their manager at Tottenham is the former Argentine defender Mauricio Pochettino.
The earthy, bitter root flavor is an acquired taste but it's catching on, recognised by health experts around the globe for myriad health benefits.
Could it be the secret to Uruguay's success so far in Russia, where they play Portugal in a last-16 game on Saturday?
"We use mate to share, to discuss, it's something that unites us. Mate helps us to get to know each other better because when someone takes mate, he talks about a lot of things and that strengthens us."
Bresciani's business is about exclusivity, the ability to produce personalised gourds.
Uruguayan and Paris Saint-Germain striker Edinson Cavani, a hunting enthusiast, "wanted a mate with deer carved into it, and escutcheon of Paris Saint Germain, the Uruguayan flag, and his name," he said.
Uruguay captain Diego Godín "called me up directly to make him a gift for Griezmann, so I did one for him." Godin and Griezmann are teammates at Europa League Champions Atletico Madrid.
Suárez offered one to Messi on the birth of his Barcelona team-mate's second child. It had his children's names, the Argentine flag and Messi's shirt-number, 10. For himself, Suárez had Bresciani engrave the smiling sun and celestial blue flag of Uruguay with the names of his wife and children. And, being a centre-forward, the Number 9.
"The boom in this customised mate began when people started to see the ones the players in the national team had. Now young players ask for mates, like Messi or Suarez have."
The cost? Around US$400. But for that, he says, you get "a jewel. These are unique pieces."