Spain's former world number one, Rafael Nadal is competing in his first event in two and a half months since the French Open, where he had to withdraw due to a wrist injury.
The 2008 Olympic Gold medalist was not going to miss the Olympics at all as he missed the Games in London four years ago due to suffering knee tendonitis that ruled him out of competitive tennis for eight months.
Gilles Simon, France's 15th seed is competing in his third consecutive Olympic Games and he's reached the third round for the third time in all of three appearances.
Simon at 31-years-old has been a former world number six in the world and he has reached two Grand Slam quarterfinals in his career, the first time in 2009 losing to Nadal, and lost to Roger Federer in the quarterfinals of Wimbledon in 2015.
Nadal has a busy schedule in his first competitive tournament back from injury as he's competing in the singles, doubles event with his compatriot Marc Lopez and in the mixed doubles with French Open champion Garbine Muguruza.
Simon is one of the underrated French tennis players on the tour as his compatriots Gael Monfils, Richard Gasquet and Jo-Wilfried Tsonga are more relatable to the fans and gain more attention.
How they got here
Nadal began his second Olympics campaign against Argentina's Federico Delbonis in the first round, and the Spaniard was impressive in his first outing in two and at half months when he ousted Delbonis' compatriot, Facundo Bagnis in the second round of the French Open and withdrew from the event in the following round.
The 14-time Grand Slam champion ended Delbonis' hopes in the first round by defeating the Argentine, 6-2, 6-1 to reach the second round in Rio.
In the second round, Nadal competed in his first match on Centre Court against Italy's Andreas Seppi who is no stranger to an upset as he defeated Federer in the third round of the Australian Open last year.
The Spaniard shown glimpses of his vintage tennis against Seppi and committed some errors in this match, Nadal defeated the Italian in straight sets, 6-3, 6-3 to reach the third round in Rio.
Simon began his third consecutive Olympics campaign against Croatia's Davis Cup hero, Borna Coric and the Frenchman recovered from an early break to defeat the young Croat, 6-4, 7-6.
Again in the second round, Simon had to come back from a break down to defeat Japan's Yuichi Sugita, 7-6, 6-2 to reach the third round at the Rio Olympics.
Their history
Nadal and Simon have played each other eight times in their careers and the former world number one has a commanding 7-1 lead in their head-to-head.
The pair has competed on hard courts and clay courts against one another.
The 2008 Olympic gold medalist defeated Simon in their first meeting ten years ago in Simon's hometown of Marseille, and the Spaniard was victorious 7-5, 6-4.
Their second meeting was in the third round of the Australian Open in 2008, and once again Nadal was victorious in straight sets with a 7-5, 6-2, 6-3 victory.
Simon gained his solitary victory over Nadal in the semifinals of the Mutua Madrid Open in 2008 in three tight sets to reach his first Masters 1,000 final.
The duo met at the Australian Open for the second consecutive year in the quarterfinals and the former world number one defeated the Frenchman, 6-2, 7-5, 7-5, and he went on to win his solitary Grand Slam singles title in Melbourne.
Another meeting occurred at a Grand Slam tournament and it was in the third round of the US Open in 2010, and the Spaniard was victorious 6-4, 6-4, 6-2 en route to winning his first US Open title which completed his Career Grand Slam.
Their first meeting on clay happened at the Monte Carlo Rolex Masters in the semifinals in 2012 and it was a 6-3, 6-4 victory for Nadal.
They had another three-set tussle in the semifinals of the Internazionali BNL d'Italia in Rome in 2014, and Nadal was victorious 7-6, 6-7, 6-2.
The Spaniard registered his fifth consecutive victory over the top ten player in the fourth round of the BNP Paribas Open at Indian Wells last year in straight sets, 6-2, 6-4.
Who wins?
Clay is Nadal's best surface which is why he is dubbed the "King of Clay" due to his dominance on the red dirt which has culminated with nine French Open titles.
However, Nadal is no slouch on hard courts either as three of his 14 Grand Slam singles title have been on this surface. The Spaniard's lefty serve works well this surface, and the Nadal's forehand is a dangerous weapon on hard courts.
Simon is known for engaging in long rallies and wearing down his opponents. The current world number 31 has reached two Masters 1,000 finals in his career, and the Frenchman has represented his country in Davis Cup before.
Both players are extremely fit, however, Simon's serve isn't the best on tour and Nadal has had a luxury over the years on breaking it on many occasions.
The 15th seed is good at absorbing the pressure and like Nadal, he is a very good defender so this match will be a contrast of two different styles, however, the former world number one is the better player but this will be his toughest test.
Nadal will be the favourite in the top half of the draw to progress to the gold medal final as 2008 bronze medalist, and world number one, Novak Djokovic was ousted by 2012 bronze medalist, Juan Martin del Potro in straight sets on Sunday.
There is an opportunity for both players to make it far in this draw, and the winner of this match will face Belgium's 8th seed David Goffin, Uruguay's 11th seed Pablo Cuevas or Brazil's Thomaz Bellucci in the quarterfinals.
This intriguing third round match will take place second on Centre Court at not before 12:30pm local time.
Prediction: Nadal in straight sets