Brazil is casting a shadow over Irish business these days. Earlier this year, we saw Brazilian juice maker Grupo Cutrale and investment firm Safra Group scupper the planned merger of Chiquita and Dublin-based Fyffes. Now, it is possible that another Brazilian investment group will end up owning Guinness.
The Harvard-educated former tennis champion behind the possible 3G takeover is Jorge Paulo Lemann who is Brazil's richest man although he has lived in Switzerland since 1999 when gunmen tried to kidnap his wife and their three youngest children.
The 75-year-old financier is no stranger to buying big food and drink companies. He helped to create world's largest brewer, AB InBev, in 2008, and then took Burger King private in 2010.
Three years later, Lemann's 3G joined up with Warren Buffett to buy Heinz in a $27bn acquisition. Earlier this year, Heinz merged with Kraft in a $46bn deal that was one of the biggest in history.
Rich lists say Mr Lemann is Brazil's richest man and worth around $25bn but he is famous for his frugality which is sometimes ascribed to the influence of his Protestant father who moved from Switzerland to Rio de Janeiro but was killed by a tram when the billionaire was a teenager.
His frugality includes banning colour photocopies, personal secretaries and reserved parking spaces but it seems to work; Burger King's profit margin has tripled since 2010.
Cutting costs is only part of the magic at 3G. The private equity group also attracts and keeps the best executives with shares options and big bonuses.
Mr Lemann's interests in the drink industry began in earnest in 2004 when he founded 3G with two colleagues and then bought the Ambev group. The same year, they bought Belgium's Interbrew.
Four years' later they bought Budweiser owner Anheuser-Busch to create AB InBev.
A deal to buy Diageo would be something of a surprise. AB InBev has long been rumoured to be eyeing rival brewer SABMiller.
Analysts said yesterday that Diageo is smaller than SABMiller, making a deal more affordable, and would also offer savings through cost cuts.
Some analysts believe that parts of Diageo, including the Gleneagles Hotel and the company's wine business, could be sold off to repay debt or avoid competition issues which raises the intriguing prospect of Guinness possibly returning to Irish hands.