MELBOURNE, Australia—The first test of Naomi Osaka’s new approach to tennis might have been when she completely whiffed an overhead to give her opponent a break point on Day 1 of the no-Novak Djokovic Australian Open. Osaka didn’t throw her racket. She didn’t roll her eyes. She smiled. “There are situations where I previously would get upset. But at this point in my life, like, I’m here because I want to be here and because I find that it’s fun for me,” Osaka said. “Might as well enjoy it while I still can.” In Osaka’s mind, the drama involving nine-time champion Djokovic’s deportation on the eve of the Australian Open was something for the players in the men’s draw to worry about. Her title defense began smoothly enough: She won the first five games on the way to a 6–3, 6–3 victory over Camila Osorio. With so much attention on …