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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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.