Japan’s Naomi Osaka beat Australia’s Astra Sharma in straight sets 6-3, 6-4 in their first-round women’s singles match at the Miami Open on Wednesday, registering her 50th win in a WTA 1000 event. Ten days after her tearful exit from the BNP Paribas Open in Indian Wells, California, where she was heckled by a spectator who shouted, “Naomi, you suck,” Osaka took one hour and 20 minutes to power past world No. 96 Sharma in two sets at Hard Rock Stadium. “I just didn’t want to let anything bother me today,” Osaka said during her on-court interview. “The last match I played wasn’t the greatest mem…