[...] as it happens, the woman who beat Williams at the French Open on Tuesday, Sloane Stephens, is making a concerted effort, at her coach's behest, to focus less on who is on the other side of the net. The 40th-ranked Stephens, who has reached the French Open's fourth round the last three years, was consistently strong from the baseline, making only 14 unforced errors to Williams' 30. The biggest victory of Stephens' career came at the 2013 Australian Open, when she defeated Williams' younger sister Serena en route to the semifinals. Winners included No.