Serena Williams appeared to be the biggest beneficiary of the upsets that took place on Thursday in her quarter of the draw at the U.S. Open. However, a draw with fewer seeded players presents Williams with a different challenge: the unknown.
Recently, it's been the unknown or unexpected player who has tripped Williams up. The more accomplished the player, the better Williams seems to play. Her 15-match, decade-long winning streak against Maria Sharapova is well documented. So are her inexplicable losses to people unheard of before they beat her.
Earlier this year, Li Na was ranked No. 2 and had just captured the Australian Open title when she played Williams in the final at the Sony Open in Miami. Williams is 11-1 against Li. So of course, Williams beat her.
This year, Williams is 18-0 against players ranked in the WTA Top 10. Yet she's struggled against lower-ranked players. She lost in the second round of the French Open to Garbine Muguruza, a talented player, but hardly a household name. Alize Cornet, a crafty player, defeated Williams in the third round at Wimbledon.
Williams had only played Muguruza once, on hard courts, before they met in the French Open. She had never played Virginie Razzano before they met at the 2012 French Open. Razzano upset Williams in the first round.
When the 2014 U.S. Open draw was announced, Ana Ivanovic and Sam Stosur were considered dangerous potential opponents in Williams' quarter.
Yesterday, Karolina Pliskova defeated Ivanovic and Kaia Kanepi beat Stosur. Aleksandra Krunic upset Madison Keys, also considered a possible tough matchup for Williams.
When informed about the upsets, Williams told reporters that her focus was on trying to get through the early rounds. "Well, you always hear about who is winning, who is losing. You hear about upsets. But for me, especially lately, I have to worry about my first round, my second round and my third round. I can't get too far ahead of myself."
Williams has been under pressure to win her 18th Grand Slam. She knows she's the favorite every time she steps onto the court. Those who play her often know this too, perhaps too well. With a history of beat downs on the brain, it could be more difficult for longtime rivals to muster the confidence it takes to defeat Williams.
Those who have never or rarely played Williams take the court with a cleaner slate. Feeling less of a burden than their Hall of Fame-bound opponent, those players can swing freely. They have nothing to lose.
A player with nothing to lose can be the scariest opponent.