Kai Trump has found herself at the center of online backlash after sharing a courtside moment from the Miami Open that didn't sit well with fans, Wonderwall.com can reveal. The criticism erupted as the 18-year-old appeared to cheer on a non-American player ahead of a high-stakes final featuring a U.S. favorite. Courtside Controversy Kai Trump posted a photo with Belarusian star Aryna Sabalenka, praising her performance.