After Brazilian football team Botafogo clinched a sensational league and cup double at the end of last season, its owner John Textor didn’t waste an opportunity to troll his naysayers. On social media the US businessman and serial soccer investor posted a photo of himself kissing the Copa Libertadores trophy, alongside a WhatsApp message from a detractor. “You don’t understand anything in football and [sic] waste of time to talk to you. And you will lose everywhere you go,” it read. Tagged in the screenshot was Paris Saint-Germain, whose Qatari president Nasser Al-Khelaifi has clashed with Textor, who is also the owner of Olympique Lyonnais in France and no stranger to public dust-ups. Yet Botafogo’s success, less than three years since being rescued from financial ruin by its American benefactor, was more than just a personal triumph for Textor. It also provided a showcase for the wave of recent investments into Brazilian football, which has attra...