On the eve of Wimbledon, where she is defending champion, the pre-tournament focus has been on an interview she gave to Rolling Stone magazine that touched on a high-profile teenage rape case in Ohio and brought her into conflict with her Russian rival Sharapova.
The piece included an account of a private conversation between Serena and her sister Venus that the reporter interpreted as an attack on Sharapova's relationship with Bulgarian player Grigor Dimitrov.
Sharapova, soundly beaten by Serena in the French Open final earlier this month, hit back on Saturday telling the world number one to keep her nose out of other people's business, adding an edge to the women's competition at the grasscourt slam.
"I made it a point to reach out to Maria because she was inadvertently brought into the situation by assumptions made by the reporter," a smiling Williams told reporters.
"I personally talked to Maria at the player party, incidentally. I said, look, I want to personally apologise to you if you are offended by being brought into my situation. I want to take this moment to just pour myself, be open, say I'm very sorry for this whole situation...
"I'm the first person to reach out to individuals and people if I feel that something may have hurt them or something may have been misconstrued."
The controversial interview quoted Serena as talking about a "a top-five player who is now in love".
It added: "She begins every interview with 'I'm so happy. I'm so lucky' - it's so boring. She's still not going to be invited to the cool parties. And, hey, if she wants to be with the guy with a black heart, go for it'."
While Serena did not deny making the comments, she was clearly angry that her private words had ended up in print.
"I've been spoiled dealing with professionalism here in the tennis world. I'm used to dealing with professional reporters... not writing or commenting on a private conversation that I may have or listening in or eavesdropping and then reporting on it.
"I was involved in a private conversation that he even wrote in the article that he said he was listening to. I take full blame and responsibility for that because I've been in the business for years and years and I should always in a way have my guard up."
Williams was in a relaxed mood ahead of making her Wimbledon bow against Luxembourg's Mandy Minella on Tuesday, blowing air-kisses with golfer Rory McIlroy as she waited in the wings to greet reporters.
A light-hearted chat about her prospects of surpassing Venus and winning a sixth Wimbledon title, however gave way after just five gentle questions.
The subject turned to her comments in the same Rolling Stone interview when she appeared to assign blame to a 16-year-old rape victim for being drunk.
She reiterated her earlier apology and said she had been in close contact with the victim's family.
"It's really important before you make certain comments to have a full list, have all the information, all the facts," she added.
"I reached out to the family immediately once the article came out, and I had a really productive, sincere conversation with the mother and the daughter. We came to a wonderful understanding, and we're constantly in contact...
"I take full responsibility. I definitely wanted to apologise to the family. They've been through so much. In talking to them and learning the whole story, you just learn how strong the young girl is, how strong she's been able to make me through this process, which I think is incredible."