WATCH: Serena walks out at Aussie Open, then walks back in

Whoops—now that's a new mishap. In Melbourne, Serena Williams walked out for her fourth-round match against Simona Halep, but then had to reverse back inside the tunnel when the announcer called out Halep's name.

"They told me to go first in the walkout, and then they called Simona's name first, so I was, like, taking a step back," Williams said. "It was, like, I'm sorry."

It's customary for the lower ranked player to walk out first, so it sounds like Williams did the right thing—she's ranked No. 16 while Halep is the world No. 1.

Ranking and order didn't matter once the two got their match underway. Williams prevailed 6-1, 4-6, 6-4 in her first big test of the tournament.

If she keeps this up, she'll be back to her more customary role at the top of the WTA in no time. It seems like her mom, Oracene, is already in that mindset.

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