Serena Williams has won the 2015 Wimbledon…

Williams overcame a slow start, eight double-faults and a nervy finish to beat Garbine Muguruza 6-4, 6-4 on today for her sixth Wimbledon title, fourth Grand Slam championship in a row and 21st major overall.

The win means Williams holds all four Grand Slam titles at once — completing the second “Serena Slam” of her career. What’s more, she secured the third leg of a calendar-year Grand Slam and, if she wins the U.S. Open, will become the first player to sweep all four majors in the same season since Steffi Graf in 1988.

Muguruza was overcome with emotion after losing to Williams in straight sets and was seen crying into her towel at the side of the court.

Williams, winning her 28th straight Grand Slam match, is now just one major title behind Graf on the Open era list and two behind all-time leader Margaret Court Smith.

At 33, Williams is also the oldest women to win a Grand Slam title in the Open era. She has now won seven major championships in her 30s.

Williams will head to the US Open next month aiming to complete the first calendar year Grand Slam of her career.