It is one of the recurring issues in tennis. How much pressure does it put on a player to go into a tournament as the world No.1? Looking at the modern history of The Championships, the answer would appear to be that occupying top spot in the world rankings presents a major challenge for even some of the sport’s greatest players.

The question becomes particularly relevant in light of Roger Federer recapturing the world No.1 position this week. If the 36-year-old Swiss is still leading the rankings come the beginning of July, the overall figures suggest that he will have a less than one in three chance of winning the gentlemen’s singles title at the All England Club.

In the 44 editions of The Championships since the official men’s world rankings were launched in August 1973, the reigning world No.1 has won the title only 14 times. In the ladies’ singles just 18 world No.1s have won the title in the 42 editions since the introduction of the women’s rankings in November 1975.

Federer, nevertheless, bucks that trend. On the five occasions when he has arrived at the All England Club as the world No.1 the only time when he has not won the title was in 2008, when he lost to Rafael Nadal in the final many consider to be the greatest match ever played.

Contrast Federer’s record, however, with those of Jimmy Connors, Ivan Lendl and Andre Agassi. Connors won the title twice, in 1974 and 1982, but failed to win it on all six occasions when he went into The Championships as world No.1. On three of them he was runner-up, to Arthur Ashe in 1975 and to Bjorn Borg in 1977 and 1978.

Lendl topped the rankings going into The Championships for five years in a row from 1986 and had a remarkably consistent record without ever winning the ultimate prize. Boris Becker beat him in three of those years, in the 1986 final and the 1988 and 1989 semi-finals.

Agassi, who was world No.14 when he won the gentlemen’s singles title for the only time in 1992, topped the rankings going into Wimbledon on three occasions, but lost in the semi-finals to Becker in 1995, to Pat Rafter at the same stage in 2000 and to Mark Philippoussis in the fourth round in 2003.

Pete Sampras meanwhile bettered even Federer’s record. In the six years when the American started The Championships as world No.1 he lost only one match, to Richard Krajicek in the quarter-finals in 1996.

The worst any men’s world No.1 has fared at Wimbledon has been to go out in the third round. Jim Courier lost to Russia’s Andrei Olhovskiy, the world No.193, in 1992, while Novak Djokovic was beaten by Sam Querrey, the world No.41, in 2016. Querrey, incidentally, is the only man in the last 20 years who has twice knocked out the world No.1 at Wimbledon, having also beaten Andy Murray in last year’s quarter-finals.

Although more women’s No.1s have won the All England Club title, the ladies’ singles has witnessed more eye-opening losses. Martina Hingis won her only All England Club singles title at the age of 16 in 1997, having gone to the top of the world rankings for the first time only three months earlier. For the next four years in a row she started The Championships as the world No.1 but failed to reach the final, her defeats including two shocking first-round losses.

In 1999 Hingis fell at the first hurdle to Jelena Dokic, the world No.129, and two years later she was beaten by Virginia Ruano Pascual, the world No.83. In 1998 the “Swiss Miss” lost to Jana Novotna in the semi-finals and in 2000 she was beaten by Venus Williams in the quarter-finals.

Steffi Graf is the only other reigning world No.1 to have lost in the first round of the ladies’ singles. In 1994 the German became the first defending champion in history to fall in the first round when she was beaten in straight sets by Lori McNeil, a 30-year-old American ranked No.22 in the world. Graf, seven times a champion at the All England Club, was world No.1 on six other occasions and the only time she lost was to Zina Garrison in the 1990 semi-finals.

Serena Williams has won four of her seven Wimbledon singles titles as world No.1 but has also suffered two surprising defeats while leading the rankings. In 2013 the American was beaten in the fourth round by Sabine Lisicki and 12 months later she lost in the third round to Alize Cornet. Lisicki had claimed another world No.1’s scalp two years earlier with her fourth-round victory over Maria Sharapova. Ana Ivanovic played only one Wimbledon as world No.1, in 2008, and was knocked out in the third round by Jie Zheng, the world No.133.

So how might this year’s world No.1 fare? Caroline Wozniacki occupies the top spot at the moment and has previous experience of going into The Championships at the head of the rankings, having done so in 2011. Like so many other world No.1s, however, she will not need reminding of her fate: the Dane was beaten in the fourth round by Dominika Cibulkova, the world No.24.