Give Serena Williams credit for one thing: Even if she is less than forthcoming about aspects of her tennis or personal life, she never has let anything affect her game for very long.

Serena Williams says she feels rejuvenated as she finishes a vacation in Croatia, tells coach Patrick Mouratoglou to "get ready"

So it should come as no surprise that Williams stuck to her story about her bizarre behavior in her doubles match with sister, Venus, that led to a withdrawal, not to mention a video of the event that went viral in a matter of minutes.

SFGate.com reported that Williams appeared to be her normal, calm and breezy self during a news conference as she prepares for the Bank of the West Classic this week in Stanford, Calif.

"I was just really under the weather," she said during a 15-minute news conference, SFGate.com reported. "I still have to go through a series of tests. Not right away - I'm right in the middle of the season - but eventually. Just to make sure it wasn't connected to anything that runs in my family, that sort of thing."

Serena Williams' coach Patrick Mouratoglou says his pupil is going through a "difficult phase"

As if anyone was buying her explanation, Serena expanded on what happened at Wimbledon. In doing so, she did try to take some pressure of Venus, who also drew criticism for failing to stop her sister from walking out onto the court for the doubles match.

"I didn't feel great walking on the court," she said. "I didn't even warm up for the match (on a practice court). Venus didn't want me to play, but that's the fight in me. I'm always go-go-go, don't stop, never want to give up. At one point she was like, 'Walk off the court!' She almost punched me (laughter). But I figured, it's just half the court, I can do it."

Serena was unable to catch balls thrown from ball boys or ball girls, couldn't bounce the ball off her racket and then threw up serves that barely reached the bottom of the net.

Yet, she went on to explain that it wasn't until later in the day that "I realized how sick I was, and I got really scared," she said. "I slept the rest of that day and night. I know people were talking about me, but I didn't hear any of that until much later, because I wasn't allowed to leave my (rental) house or my bed for a few days. Once I was able to travel, I didn't meditate on it too long. I'd already moved on."

Angelique Kerber, who saw Serena practice, said she witnessed the Serena of old.

"From what I saw, she's back for sure," said Kerber, the world's No. 8-ranked player who, like Serena, has drawn a bye into the second round. "We'll see, but I think she'll be the favorite here."

Serena likely knows she has to make a deep run here to at least temporarily put a halt to the Wimbledon questions. But for now, everything's fine.

Really.

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