Ryo Ishikawa, the hugely popular Japanese star who rekindled memories of his wunderkind days with three wins in 2019, has fired a warning to his rivals at next week’s SMBC Singapore Open. Ishikawa, the so-called ‘Bashful Prince’, said that he is swinging freer than during his previous visits to Sentosa Golf Club and predicted even better results in 2020. “I …