Muguruza is only the second Spanish woman after Arantxa Sanchez Vicario to reach number one and by claiming the Wimbledon title became the first player to beat both Serena and Venus Williams in major finals, having beaten Serena to win the 2016 French Open.
"Becoming the WTA number one in the world is a dream come true," Muguruza told the WTA's website. "Every birthday wish was always the same as I blew out the candles - to become the best.
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"There is a lot of work behind this achievement and a lot of love and passion for this sport. There's also a lot of hard moments along with the great moments."
Muguruza is competing at the WTA Finals in Singapore next week.
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