Serena Williams says she's "Team Djokovic" as he launches a players union. Serena: "I would be really interested to learn more about what everything is about [with Novak Djokovic's player union] because I feel like I can't really have an opinion unless I understand more deeply. I'm obviously always Team Djokovic, but at the same time I've been on the WTA Tour for 30 years and I know a lot of stuff that's happening there. I would like to -- yeah, I can't really comment on that. I do feel he has some very strong opinions that are often true."