Between 2002 and 2003, Serena Williams and Venus Williams faced each other in four successive Grand Slam finals.
Here, Last Word on Tennis is recounting their encounters at the highest level.
French Open 2002
By the time Serena Williams arrived in Paris in 2002 she had yet to add to her maiden slam title of the US Open in 1999.
She was however World No. 3 having won her first clay court tournament at the Italian Open, defeating Jennifer Capriati and Justine Henin in the process.
In contrast, her older sister was a four-time major winner, having triumphed at Wimbledon and the US Open in 2001 and 2002.
Earlier that year she had twice held the World No.1 ranking for three years before Capratri regained it but she warmed up for Paris by winning in Hambury and came in as the World No. 2.
The younger sibling, Serena lost only one set en route to the quarter-finals where she dispatched Mary Pierce for the loss of two games.
In the last-four she was up against defending champion and top seed Capriati but recovered from losing the opening set to claim an impressive victory 3-6, 7-6, 6-2.
Venus eased into the quarter-finals, where she would face sixth seed Monica Seles, without dropping a set.
This run continued with a straight sets victory and after reaching her first Roland Garros semi-final, went one further after comfortably seeing Argentine Clarisa Fernandez.
With both of them looking for their first title in Paris, as expected, it was a tight first set which Serena edged 7-5.
However, the second set was more one-sided as the younger Williams’ had too much, comfortably winning 6-3 to win her second major.
As a result of her triumph in Paris, the Williams sisters were the top two ranked players in the world.
Serena’s best run at the All England Club had come two years previously, reaching the semi-finals only to lose in straight sets to her sibling.
Venus on the other hand, was the two-time defending champion having beaten Lindsay Davenport and Justine Henin in successive finals.
Serena extended her straight sets run at Grand Slams as she eased into a quarter-final meeting with rising star Daniela Hantuchova.
She beat the Slovakian handily to set up a last-four encounter with Amelie Mauresmo which was surprisingly even more one-sided with Williams losing just three games.
On an impressive winning streak at Wimbledon, Venus showed her confidence by striding into the last-16 for the loss of just one set.
Here she thrashed little-known Elena Likhovtseva to play Justine Henin in the semi-final which was an equal non-event with the American victorious 6-3, 6-2.
For the second straight slam final the Williams sisters would meet and as in Paris, it was a close first set with Serena prevailing in a tie-break.
Again, the younger Williams sealed a straight sets victory giving her a first Venus Rosewater dish and memorably ending her sister’s winning streak.
US Open 2002
Serena had little match practise ahead of Flushing Meadows, losing in the quarter-finals in the JPMorgan Chase Open, ending a 21-match winning streak.
In contrast the elder Williams sister came into the final slam of the year into encouraging form, winning titles San Diego and New Haven for the third consecutive year.
Now the World No. 1 for the first time, Serena belied her lack of matches by breezing into the quarter-finals losing just 10 games.
For the second consecutive slam she met Hantuchova and again swept her aside to play fellow American Lindsay Davenport in the last-four.
Here she comfortably won to reach her third final in four years.
Apart from being taken to three sets by compariot Chanda Rubin, Venus reached the last-16 without too much fuss, before easing past Monica Seles.
In a topsy-turvy encounter with Mauresmo, she eventually came through in three sets to set up a rematch of the previous year’s final.
That final had been won by Venus in straight sets but she would have to go the distance to retain her title after losing the opener 6-3.
However, she could not cope with her sister’s movement and fierce groundstrokes as the title was sealed 6-3.
For the second consecutive Grand Slam Serena had triumphed without dropping a set and was edging closer to holding all four Slams at once.
This victory in her native America made Williams only the third player in tennis history to win the “Surface Slam”, three Slam titles on three surfaces in the same calendar year, after Navratilova and Graf.
Australian Open 2003
To the start the following year the sisters travelled to Melbourne for the Australian Open.
The year before Serena had been absent through injury and had a patchy record with her best result coming in 2001 when she eventually lost in the quarter-finals to Martina Hingis.
As for Venus, she had also yet to triumph in Melbourne but had gone further than her sister, losing to Serena’s conqueror Hingis in the last-four.
After coming from a set down in the first round, Serena’s progress to the quarter-finals was serene.
She continued her flawless run in an all-American encounter, beating Meghann Shaughnessy 6-2, 6-2.
Next she met Belgian Kim Clijsters but again fought back from a set down, then 5-1 in the decider, winning 7-5 after saving two match points.
Venus’ impeccable tennis took her to the last-16 in style where she accounted for Hantuchova to set up a meeting with, a change of name, Justine Henin-Hardenne.
Considering it was the fifth seed against the second, it was unexpectedly straightforward with the result following the rankings 6-3, 6-3.
This resulted in a fourth successive final between the pair and true to previous encounters, the first set was an even affair with Serena edging a tie-break.
However, for the first time in the finals, it would go the distance as Venus hit back to claim the second 6-3.
On the brink of history, Serena fought back and clinched the ‘Serena Slam’ winning the decider 6-4.
Williams’ win in Melbourne ensured she became the fifth woman to hold all Grand Slam singles titles simultaneously, joining Maureen Connolly Brinker, Margaret Court, Steffi Graf, and Martina Navratilova.
These four finals showcased the best of both Venus and Serena when they were undoubtedly the best two players in the world.
Following this run, the sisters won further slams with Venus currently having won seven and Serena 23 and the fact they are still playing at 39 and 38-years-old respectively shows their outstanding professionalism and longevity.