MELBOURNE, Australia — Flat on her back, her sore right ankle raised and her hands covering her face, Serena Williams tried to block out thoughts that her bid for a third straight Grand Slam title might be ruined.
After a dominating run the last six months, Williams was a big favorite to win the Australian Open. Suddenly, though, there seemed a way for her to be gone in the first round.
‘‘I almost panicked, and I thought, ‘I can’t do that,’ ’’ she said. ‘‘I just have to really remain calm and think things through.’’
The stats showed this was nothing more than a stroll — a 6-0, 6-0 wipeout in 54 minutes of No. 110-ranked Edina Gallovits-Hall at Melbourne Park on Tuesday. Williams conceded only six points in the second set.
But this match took significantly longer to complete given the medical timeouts. And while the score may have been painful to her opponent, there was plenty of pain to go around.
The first set was 4-0 after 19 minutes at Hisense Arena when her tumble near the baseline diverted attention on Day Two from center court, where a day session featuring Roger Federer, Andy Murray, and women’s champion Victoria Azarenka was under way.
After some deep breaths, the 31-year-old Willlams pulled herself together, got to her hands and knees for a few minutes and gradually to her feet.
Her already heavily taped ankle was assessed and retaped. She went back on court and won the next four points to get herself to another changeover, and more attention from the doctor. She went back and held another service game to clinch the set, giving her time for more treatment.
‘‘A very similar thing happened to me last year, almost on the same side, the same shot,’’ Williams said, referring to a fall that forced her to pull out of the Brisbane International last year and contributed to her fourth-round exit at the Australian Open.
Her subsequent trip to the French Open ended in her only first-round exit at a Grand Slam tournament, more painful mentally than physically. Stunned by the defeat in Paris, she hired a new coaching consultant, amended her training regime, and won Wimbledon, the London Olympics, the US Open, the season-ending championship and added the 2013 Brisbane International title to her collection.
Now she has 36 wins from her last 37 matches. And she decided that she’d ice her ankles, wait for the swelling and bruising, and think about medical tests later.
‘‘I would really rather not know,’’ she said. ‘‘One year I won this tournament and had two bone bruises in both knees. I had no idea. I just knew I was in pain. I think sometimes what you don’t know cannot hurt you.’’
She expects to at least start her second-round match Thursday against Spain’s Garbine Muguruza, who beat Magdalena Rybarikova of Slovakia, 4-6, 6-1, 14-12. The final set lasted more than two hours.
‘‘Oh, I’ll be out there,’’ Williams said. ‘‘I mean, unless something fatal happens to me, there’s no way I’m not going to be competing.’’
If results go according to rankings, Williams will meet top-ranked Azarenka in the semifinals.
Even if Williams is on one leg, Azarenka is still wary of the 15-time Grand Slam champion. After her 6-1, 6-4 win over Monica Niculescu, she checked the progress in the Williams match.
‘‘I heard she won love and love, so what kind of injury are we talking about?’’ she joked.
She progressed along with former No. 1 Caroline Wozniacki, who beat Sabine Lisicki of Germany, 2-6, 6-3, 6-3, and American teenager Sloane Stephens, who beat Simona Halep of Romania, 6-1, 6-1.