Tokito Oda won his third Grand Slam wheelchair tennis singles title, while another 17-year-old Japanese player, Rei Sakamoto, took the junior boys’ singles crown at the Australian Open on Saturday. In their respective finals, Oda defeated Britain’s Alfie Hewett 6-2, 6-4, while Sakamoto came from a set down to beat Jan Kumstat of the Czech Republic 3-6, 7-6(2), 7-5 at Melbourne Park. Oda got off to a brilliant start to the Paris Paralympic year, converting four of 11 break points. “I was able to play aggressively,” the left-hander said. “I was able to do what I wanted to do on the court. I’m ha…