Serena Williams has come from a set down to defeat Eugenie Bouchard in her second-round match at the Cincinnati Open.
The Canadian shocked the world number one by breaking for a 4-2 lead in the first set and holding her nerve to clinch it 6-4.
However, Williams refocused her efforts to take the second set 6-2 before winning the decider by the same scoreline.
She will face the winner between Mona Barthel and Maria Kirilenko in the third round.