World number one women tennis player Serena Williams was disappointed by her defeat against Ukraine's Elina Svitolina (6-4, 6-3) and regretted the missed opportunity at the 2016 Olympics."It was a great opportunity. It didn't work out the way I wanted it to be, but at least I was able to make it to Rio. That was one of my goals," the reigning Olympic gold medallist said on Tuesday, reports Efe news."It was awesome and fun, but it's over now," said the 35-year-old tennis superstar.About the match, the world number one said: "Obviously, I am very disappointed. The better player won today but I can't wait for next time. That will be a really good match and I look forward to it," Williams said.