if you knit pick anything you can find something wrong with it, i think it did look like Serena (well as much as a cartoon can) if he drew the exact same photo sor another tennis player and had white skin no one would be saying a work. Anyway it's a point of view i guess, you think its racist i think its not.Basically because it caricatured generic characteristics of a race rather than caricaturing particular features of an individual, and in this case used features that have been drawn over centuries to demean black people and highlight how they are less human than white people.
There has been some interesting discussion out of this about how convinced many Australians are that nothing can be racist if it wasn't intended to be racist. There is a real need to listen more and consider the effects rather than the intent.
On another note,
Women tennis players make more per hour then Men at grand slams, they play best of 3 sets and the prize money is the same, this is a disadvantage to men and needs to change, also if Serena played on a 100% level playing field she wouldn't have a single grand slam to her name and no one would know who she is because she would never have beaten the likes of Federer, Nadal, Djokovic and probably anyone in the top 100. So her complaining about things being sexist needs to be looked at from a different angle.