Novak Djokovic can become just the eighth man to complete the career Grand Slam with a maiden French Open victory, but the world number one fears fate may conspire against him in Paris.
Djokovic, who turned 28 on Friday, is the overwhelming favourite to lift the Coupe des Mousquetaires and claim his ninth career Grand Slam title.
Victory would take him alongside Fred Perry, Don Budge, Rod Laver, Roy Emerson, Andre Agassi, Roger Federer and Rafael Nadal as a winner of all four majors.
It would also take him halfway to a calendar Grand Slam, a challenge so daunting that only Budge (1938) and Laver (1962 and 1969) have managed to pull it off.
Djokovic comes into Paris riding a 22-match winning streak, a season which has already seem him capture a fifth Australian Open as well as Masters titles in Indian Wells, Miami and on clay at Monte Carlo and Rome.
However, the Serb has been in this situation before.
In 2011, he entered the French Open as hot favourite but saw a 43-match winning sequence ended by Federer in the semi-finals.
A year later, Djokovic was defeated by Nadal in a four-set final which was completed on the third Monday because of rain.
In 2013, it was the Spaniard who again came out on top, this time in the semi-finals despite Djokovic having led 4-2 in the fifth set.
Twelve months ago, Nadal claimed his ninth title as Djokovic wilted once more in the championship match.
No surprise then to see Djokovic, whose overall 2015 record reads 35 wins and just two losses, trying to contain the hype ahead of his 11th French Open.
His caution increased after Friday's draw which lined him up to possibly face Nadal in the quarter-finals and third seed Andy Murray in the semi-finals.
"I have had this particular situation before, and especially in the last two years where I was coming into Roland Garros and people speculating, is this the year or not?," said Djokovic who faces Finnish veteran Jarkko Nieminen in the first round.
"I was very close a few times. Didn't manage to do it, but that doesn't discourage me to not keep on going. I'm here once again with a purpose, with a reason, and I will try to get myself in a position to win."
Nadal goes into the French Open with his astonishing record of nine titles, 66 wins and just one loss in Paris.
But the 28-year-old defending champion has slumped to seven in the world, his lowest ranking since 2005, the year of his maiden Roland Garros title.
Nadal heads for Paris without a European clay-court title for the first time in a decade.
"I don't need to lie to create better expectation. When I say I don't know what's gonna happen, I really don't know what's gonna happen," said the 14-time major winner who begins his 11th Paris campaign against 18-year-old Frenchman Quentin Halys, the world number 304.
"I am gonna try to put my game in a position that's gonna give me the chance. If I am able to do it, I have enough experience here."
Federer, who meets lucky loser Alejandro Falla of Colombia in Sunday's opener, completed the career Grand Slam with his only French Open triumph in 2009.
A five-time finalist, the 33-year-old has endured steadily diminishing returns in Paris with a 2011 runners-up spot followed by the semi-finals in 2012, a quarter-final exit in 2013 and a shock fourth round defeat to Ernests Gulbis 12 months ago.
Federer, who won the last of his record 17 majors at Wimbledon in 2012, believes it would be foolish to write off Nadal.
"It's going to be best-of-five sets. We know how tough Rafa is physically and mentally. He is the favourite still to me."
World number three Murray has surprisingly emerged as Djokovic's greatest threat.
After failing to lift a clay-court trophy in 10 years of trying, the Scot suddenly won two in the space of six days in Munich and Madrid.
The 28-year-old has a 10-0 record on clay this year and has twice been a semi-finalist at the French Open.