Sport is often cyclical in its nature. Periods of dominance come and go as the competitive landscape shifts in favour of differing competitors.
Novak Djokovic saw his supremacy reach its pinnacle at the 2016 French Open, but a dramatic and unexpected drop-off in form quickly followed as he struggled with a persistent elbow injury.
The 15-time grand slam champion returns to Roland Garros this year with a chance to come full circle and reaffirm his place as the leading force on the ATP Tour by holding all four grand slams simultaneously for the second time in his career. He would be just the second man to do so.
We chart Djokovic's journey from his highest point to his lowest, and potentially back again.
Djokovic moved to the top of the world rankings for the third time in his career when he won Wimbledon in 2014 and it was the start of an incredible period that saw him fail to win just two of the next seven majors.
He retained his title at the All England club the following year with a final victory over Roger Federer, then a seven-time champion, to underline his status as the man to beat.
Djokovic added the 2015 US Open and started the next season by winning the Australian Open, meaning he went to Roland Garros with the chance to become first male to hold all four majors simultaneously since Rod Laver in 1969.
The Serbian may have felt his best chance to complete the career Grand Slam had passed him, having eliminated 'King of Clay' Rafael Nadal in the 2015 quarter-finals only to lose the showpiece - for the third time in his career - to Stan Wawrinka.
But with Federer opting not to play at Roland Garros amid knee and back issues and Nadal struggling with a wrist injury, Djokovic was finally able to get his hands on La Coupe des Mousquetaires.
A surprise defeat to Sam Querrey in the third round at Wimbledon brought Djokovic swiftly crashing back to earth.
Although he responded by winning the Rogers Cup, he was eliminated by a returning Juan Martin del Potro in the first round of the Olympic Games, lost the US Open final to Wawrinka and was beaten at the ATP Finals by Andy Murray, who consequently ended 2016 as world number one.
Djokovic split with coach Boris Becker and got rid of the rest of his team after being humiliated by Denis Istomin in the second round of the Australian Open – his earliest grand slam exit since 2008.
The appointment of Andre Agassi, someone who managed to continue winning majors after completing the career Grand Slam, failed to spark a recovery in his form and he retired from a Wimbledon quarter-final against Tomas Berdych due to an elbow injury, which ended up curtailing his season.
Djokovic underwent surgery on his elbow after losing to Hyeon Chung in the fourth round at the 2018 Australian Open and continued to struggle upon his return, failing to get beyond the third round at Indian Wells, Miami, Monte Carlo, Barcelona and Madrid.
Although Marian Vajda had been brought back into his team, his lowest ebb came with a quarter-final loss to Marco Cecchinato at the French Open. A disconsolate Djokovic was at a loss to explain his slump after the high experienced at Roland Garros just two years prior and suggested he could skip the grass-court season.
His decision to persevere in the wake of that humbling loss proved pivotal.
Djokovic reached the final at Queen's before finally ending his grand slam drought at Wimbledon, a sensational five-set victory over Nadal in a semi-final that spanned two days making it clear he was back at his best.
The Serbian revealed that a five-day hike with his wife in the French Alps after his defeat to Cecchinato had helped him "recalibrate", and he looked unstoppable as he beat Federer in straight sets in the final at Cincinnati before winning the US Open.
He returned to the top of the rankings for the first time in just over two years in November 2018 and a ruthless straight-sets triumph against Nadal wrapped up this year's Australian Open.
Having triumphed in Madrid and reached the final in Rome, where he took Nadal to three sets despite being bagelled in the first, he now has an opportunity to complete an incredible story and become only the second man to hold all four majors on two separate occasions.