Serena Williams has beaten sister Venus 6-4 6-4 in the Australian Open final to become the most-successful women’s player in professional tennis history.

Williams overcame a shaky start to land an unprecedented seventh Open title and open-era record 23 grand slam singles crown with an emotional 6-4 6-4 triumph on Saturday night.

The all-conquering American not only eclipsed German great Steffi Graf’s modern-day mark of 22 grand slam titles, but also regained the world No.1 ranking she’d relinquished to Angelique Kerber last September.