So much for the Williams' conspiracy theory.

Two days after No. 1-ranked Serena Williams lost to No. 78 Jana Cepelova in the first round of the Family Circle Cup in Charleston, S.C., sister Venus Williams also bowed out.

On Thursday, Eugenie Bouchard, the No. 6 seed, knocked out Venus 7-6, 2-6, 6-4 to advance to the quarterfinals, according to CBC Sports.

The Williams sisters have been battling talk about conspiracies since both of them became dominant tennis players. Serena's loss to Cepelova certainly could've been put in that category.

But Venus was on the other side of the draw in the Family Circle Cup and had been battling what she described as a "bug," tennis.si.com reported. She struggled to win her first two matches and also developed a blister on her foot to beat Chanelle Scheepers 7-5, 7-5 in the second round.

Bouchard's victory wasn't an upset. Venus was seeded just 11th in the tournament, and Bouchard has a higher ranking (No. 28) in the WTA than the elder Williams (No. 28).

Venus, who has been dealing with Sjogren's syndrome since 2011, won her first tournament in two years when she defeated Alize Cornet in the finals of the Dubai Championships on February. Cornet, who defeated Serena in the semifinals, won just three games against Venus in the finals, conjuring speculation that the younger sister purposely lost to allow Venus her moment in the spotlight.

Venus has enjoyed fewer and fewer of those as time has passed.

The win was big for Bouchard, who has just won four tour-level matches since the Australian Open, according to tennis.si.com. Her claim to fame, however, still is in the form of a post-match interview at the Australian Open in which she defeated Ana Ivanovic.

During that interview, Bouchard was booed after revealing her dream date would be enigmatic pop icon Justin Bieber.

If only the Williams sisters' issues were that trivial.

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