Serena Williams' bid to become the most successful female player to grace a tennis court has been derailed in recent times by an unexpected trend of unheralded players winning grand slams.

The world number one has been stuck on 21 grand slam titles – one behind Steffi Graff and three behind Margaret Court, who has the most grand slam wins in the history of the women's game – since her 6-4 6-4 win over Garbine Muguruza in last year's Wimbledon final. 

Williams reached the semi-finals at the US Open in 2015 and the final of the Australian Open in January, only for her push for those titles to be brought to an end by Roberta Vinci, who went on to lose to Flavia Pennetta in the Flushing Meadows showpiece, and Angelique Kerber.

But Williams now heads to Roland Garros, where she has won in two of the last four years, and with major rival Maria Sharapova reduced to the role of spectator after her involvement in the meldonium saga, normal service will be expected to be resumed in the French capital.

Of the grand slam final regulars in the draw, Victoria Azarenka would appear to be the player with the best chance of defeating Williams, having done so at Indian Wells this year.

However, over three sets the two-time Australian Open champion has regularly struggled to close out matches from winning positions against Williams, with defeats in the third round at Roland Garros and the quarter-finals of Wimbledon serving as prime examples of Azarenka's failings when forced to go the distance with the American.

Agnieszka Radwanska is another player with experience of reaching the latter stages of grand slams, but has never beaten Williams and lost to her in the Wimbledon showpiece four years ago.

Petra Kvitova has the grand slam pedigree with two Wimbledon titles and semi-final showings at the Australian Open and French Open to her name, yet she has just one win in six versus Williams and – since reaching the semi-finals in Stuttgart – has endured an underwhelming clay-court swing.

Simona Halep would be far from a surprise winner but, of the established order, the 2014 French Open finalist may be best placed to challenge Williams for the title after winning in Madrid in the lead-up to the tournament, although she also has just a sole win against the 34-year-old in eight meetings.

With two-time US Open finalist Caroline Wozniacki pulling out through injury and Kerber approaching Roland Garros on the back of early exits in Madrid and Rome, it may be an unexpected name that will have to step up and prevent Williams from winning her fourth French Open if the likes of Azarenka, Kvitova and Halep are unable to contend.

Few will tip Muguruza – despite being world number four – to challenge for the top prize, but the Spaniard was far from embarrassed against Williams at Wimbledon and has scored a triumph over her the French in 2014.

Muguruza's confidence will have been boosted by a run to the semi-finals in Rome that was ended by Madison Keys, who forced Williams into a tie-break in the final of that event before succumbing to a straight-sets defeat.

Of the outsiders it is Keys who is most likely to match Williams for sheer power. The quality of Williams told in the end in their encounter, though, and the smart money is on her jumping for joy again come finals day on Court Philippe Chatrier regardless of who she is facing.