Few have come to define a sport as much as Serena Williams came to define tennis over her extraordinary career.

With 23 Grand Slam singles titles, 73 overall singles titles, and 319 weeks as world No 1, Serena is not only one of the greatest tennis players of all time but one of the greatest sportspeople of all time.

Two years on from her retirement, we’re looking back at some of the players who helped push her to those heights – by ranking her seven greatest rivalries.

To help determine this ranking we’ve factored in the number of meetings, the importance of those matches, the competitiveness of the head-to-head, the attention these match-ups created, and the status Serena’s rivals themself hold.

Agree or disagree? Make sure to let us know in the comment section below!

7) Lindsay Davenport

H2H: Serena leads 10-4

We start our countdown with Davenport, a three-time Grand Slam champion and former No 1 who faced Serena 14 times across her career.

Serena certainly had the edge in their rivalry, winning 10 of their encounters, but several of their matches were close; six of their matches went to a third set.

Davenport won their first meeting in Chicago back in 1997 and also won a US Open quarter-final between the two in 2000.

However the 23-time Grand Slam champion prevailed in their sole Slam final – the 2005 Australian Open – and won three of the four US Open matches they played between 1999 and 2002.

6) Victoria Azarenka

H2H: Serena leads 18-5

This was a head-to-head largely controlled by Serena, but there is no doubt that Azarenka pushed her more than anyone else across the 2010s.

A formidable competitor during her peak, two-time Australian Open champion Azarenka beat the American in four WTA 1000 finals – more final victories at that level than anyone else over Serena.

Serena certainly had the edge at a Grand Slams, though, losing just one of their 11 major matches, and winning two thrilling US Open finals between the two in 2012 and 2013.

With 23 matches contested between the two, this was the second most-played rivalry of her career.

5) Maria Sharapova

H2H: Serena leads 20-2

One of the most famous – perhaps infamous – rivalries in WTA history, there is a lot that could be said about Serena and Sharapova’s rivalry.

It was not ultimately that competitive a rivalry in terms of the head-to-head, with the 23-time Slam winner winning their final 19 meetings after losing the Wimbledon and WTA Finals final in 2004.

But there was always a sense of anticipation when the two, among the biggest tennis stars of all time, met, with four of their 22 meetings coming in Grand Slam finals.

And though they are on good terms now, it was obvious that tension was high between the two during their respective peaks – something that Serena perhaps harnessed to her advantage.

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4) Jennifer Capriati

H2H: Serena leads 10-7

Capriati is not often in the conversation regarding Serena’s greatest rivals but the three-time Slam champion had more success than most, with a solid win in seven matches against her compatriot.

The final 15 of their 17 matches were all in or past the quarter-final stage of some of the tour’s biggest tournaments, highlighting how significant many of their matches were.

Capriati won four of their first five matches, but Serena then won eight straight matches, including two Miami Open finals and a thrilling 2002 French Open semi-final.

However, seven of these eight wins were in three sets, and former world No 1 Capriati bounced back to win three of their last four matches – including French and US Open quarter-final triumphs in 2004.

3) Martina Hingis

H2H: Serena leads 7-6

One of the greatest players of the late 1990s and early 2000s, five-time Grand Slam singles champion Hingis proved to be one of the most crucial rivals for Serena in the early part of her career.

A first meeting at the Miami Open in 1998 ended with the Swiss narrowly winning a third-set tiebreak, and it was Hingis who Serena beat to win her first Slam at the 1999 US Open.

Momentum in the head-to-head swung back and forth between the two and former world No 1 Hingis was 6-4 up after defeating her rival 6-2, 3-6, 8-6 in an epic Australian Open quarter-final in 2001.

However, Serena won their final three clashes to seal a narrow overall lead, sealing a crucial victory in their final clash at the 2002 Miami Open.

2) Justine Henin

H2H: Serena leads 8-6

Matches between Serena and seven-time major champion Henin were some of the most memorable and crucial of the 2000s.

The US star won four of their first five encounters, including final victories in Berlin and Rome, but the tables began to turn as the decade progressed – most notably with Henin’s controversial 2003 French Open semi-final victory.

Serena won the 2007 Miami Open final to move 6-3 up in the head-to-head but proceeded to lose three straight major quarter-finals to Henin, with the Belgian going on to win two of those tournaments.

Their 14th and final meeting was fittingly their biggest, the American winning a three-set Australian Open final in 2010 to move 8-6 in front – though she was pushed hard by Henin across her career.

1) Venus Williams

H2H: Serena leads 19-12

Could anyone else have been at No 1 in this ranking?

Venus was not the most competitive rival of Serena’s career, with the latter winning 19 of their 31 contests, but no one understandably proved more of a challenge than her to beat.

Across a staggering 22-year period, matches between the two enthralled tennis fans and while it was obviously awkward for them to face off, they regularly delivered on the game’s greatest stages.

They met in nine major finals – Serena winning seven of them – and 12 WTA finals overall, with 16 of their 31 matches coming in Grand Slam tournaments.

Without Venus, there would be no Serena, and this rivalry more than any other helped the latter make history time and time again.

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