Serena Williams overcame a shaky start to her Olympic defense to ultimately dominate Australia's Daria Gavrilova in Rio de Janeiro.
The top seed — and four-time Olympic gold medalist — had to scrap to hold serve in the opening game, and then coughed up an immediate break of serve, but quickly settled into a rhythm to beat the world No. 46 6-4, 6-2.
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“It feels good to win my first match," Williams said. "No one wants to go out in the first round. It’s always a little tricky and you always want to at least win a match, so I feel really good about that. It wasn't that easy. (Gavrilova) has a lot of big wins and she plays really well."
Gavrilova found early joy by coming to the net and intercepting Williams' power strokes, but she was pushed further and further back as the world No. 1 took control.
Williams remained shaky on serve, broken to love when 5-3 up in the opener, but her 22-year-old opponent could not make it count and Serena swiftly broke back to take a 1-0 lead.
“It (the first set) was really tight and the (windy) conditions were really tough," Williams said "We played some wonderful points in the first set. The wind was really, really tough.”
The second set was one-way traffic, with Gavrilova frantically flying across the baseline as Williams boomed shots around the court. The Australian tumbled on several occasions as her efforts became more frantic.
Her fatigue showed through as Williams wrapped up the final set on the back of five points, each earned by wayward Gavrilova shots.
Williams' older sister Venus was stunned in the first round by Kirsten Flipkens on Saturday and the three-time defending doubles champions will begin the defense of their crown later on Sunday against Czech pair Lucie Safarova and Barbora Strycova.