On the day she matched Steffi Graf’s Grand Slam singles title haul, Serena Williams provided a reminder of what clearly sets her apart from the German.

While Graf claimed a solitary Grand Slam doubles title Williams and big sister Venus have been as dominant a partnership, whenever they have chosen to play together, as they have been collectively in singles play over the past 17 years.

Back in tandem, targeting a fourth Olympics doubles gold medal in Rio in August they went into the women’s doubles draw at Wimbledon as the least likely unseeded pairing in the history of the sport. Their target was a 14th Grand Slam title together and, in spite of the effort it has taken for Serena to achieve her historic singles win, perhaps even more so for Venus to reach her first Grand Slam singles semi-final for six years, they urged one another on as ever throughout the fortnight.

In keeping with what had gone before, during the younger sister’s singles defeat of Angelique Kerber, they found themselves engaged in a high quality match with Hungary’s Timea Babos and Kazakhstan’s Yaroslava Shvedova, taking the first set 6-3 with the singles champion’s serve the only one that was unbroken in that opener. Nor did that change in the second as they duly completed a 6-3, 6-4 win.

So, as we still await the final answer to one career-defining question, we can acknowledge that we have long known that to another.

Is Serena Williams the greatest women’s singles player of all-time? Statistically, at least, we must wait and see.

Is she the greatest women’s tennis player of all-time? Indisputably.

Meanwhile a young woman who had, just a year or two back, looked like Britain’s best women’s prospect gained consolation for her latest early singles exit when Heather Watson reached the Mixed Doubles final with Finnish partner Henri Kontinen.

Watson - who has been replaced as British number one by Johanna Konta - and Kontinen beat Latvia’s Jelena Ostapenko and Austria’s Oliver Marach 7-6, 6-3 in their semi-final, to earn a Centre Court meeting with Colombian Robert Farah and Germany’s Anna-Lena Groenfeld.