Update: Speaking to HuffPost UK, a spokesperson for Sports Illustrated said: "We did nothing to change the integrity of the cover image or likeness of Serena Williams."
Serena Williams may have been named Sports Illustrated's 2015 Sportsperson of the Year, but the publication has come under fire for its cover photo of the star.
On social media many have accused the magazine of Photoshopping the 34-year-old's photo in order to make her thighs and face appear thinner than they are in real life.
Sports Illustrated has said it chose Williams for the coveted award as she won 53 of her 56 matches this year, but fans on Twitter have argued that the cover photo "undermines" her sporting achievement.
Many online have also compared the Sports Illustrated cover to the recent Pirelli shoot, in which Williams appeared semi-nude in a series of un-retouched images of inspirational women.
Commenting on the latest cover, Rivkie Baum, editor of plus size magazine SLiNK, said she thinks it's "incredibly sad that Sports Illustrated feels that they have to subject Serena's incredible body to the strict and flawed beauty ideals of the fashion industry".
"While Serena should be celebrated as a powerful and successful, strong, fit and healthy woman, Sports Illustrated have chosen to ignore this," she told HuffPost UK Lifestyle.
"It is sadly a missed media opportunity to reinforce that healthy, strong and beautiful bodies come in different sizes and deserve to be celebrated.
"We need to remind women that they can and should be valued for their achievements not appearance."
The Huffington Post UK has contacted Sports Illustrated for comment, but has yet to hear back at the time of publication.
In a tweet, Sports Illustrated said: "Serena’s cover shot was her idea, to express her own ideal of femininity, strength, power."
Update: Speaking to HuffPost UK, a spokesperson for Sports Illustrated said: "We did nothing to change the integrity of the cover image or likeness of Serena Williams."