Novak Djokovic buried his grief to advance to the quarter-finals of the Monte Carlo Masters on Thursday, just hours after learning of the death in Serbia of his beloved grandfather.
The world number one elected to take to the court against Alexandr Dolgopolov of the Ukraine after suffering the heart-breaking blow at training in the morning.
His match, interrupted by the fourth rain shower of the day at the Monte Carlo Country Club, eventually ended with a 2-6, 6-1, 6-4 win and a pleading look to the Mediterranean skies from the distraught star.
Djokovic was said to be close to grandfather Vladimir and sheltered with him and other family members during the NATO bombing of Belgrade in 1999.
After leaving the court in silence organisers the ATP released a statement which read: "Novak Djokovic would like to ask for your understanding.
"As you know, he lost his grandfather today just before the match, and it was very hard for him to play. After he won, he just felt totally exhausted physically, mentally and emotionally."
There was no word as to whether the world number one would continue in the tournament which he missed last year during a record-setting season of ten titles including three of the four grand slams.
He is due to face Holland's Robin Haase in Friday's quarter-finals.
Second seed Rafael Nadal continued his quest for an eighth straight title at the tournament as he dispatched Mikhail Kukushkin of Kazakhstan 6-1, 6-1.
Nadal will next face Stanislas Wawrinka of Switzerland for a place in the semi-finals.
World number two Nadal needed just 60 minutes to see off Kukushkin, breaking serve five times from six opportunities and dropping only six points on serve.
He improved his career record in Monte Carlo to 41-1, his only defeat coming against Guillermo Coria in the third round in 2003.
"The match started in the perfect way," said Nadal. "I played much better than yesterday, in my opinion. More aggressive, more solid. My serve was much better. The return, too. In general today I was very happy with how I played."
Meanwhile, Andy Murray's apparent jinx on opponents continued, with the third seed advancing when Frenchman Julien Benneteau went down with an ankle injury and subsequent broken elbow.
Murray got a rare two walkovers last month in Miami, when Canadian Milos Raonic was injured before their third-round encounter and Nadal was unable to play their semi-final due to the knee problems which continue to haunt him.
Fourth seed Jo-Wilfried Tsonga saved nine break points to beat Fernando Verdasco of Spain, the 13th seed, 7-6 (9/7), 6-2.
He became the first French player into the last eight since Richard Gasquet five years ago and was then joined by compatriot Gilles Simon, who upset seventh seed Janko Tipsarevic of Serbia 6-0, 4-6, 6-1.
The two Frenchmen meet on Friday for a last-four place.
Sixth seed Tomas Berdych rallied past Japan's Kei Nishikori 2-6, 6-2, 6-4 to line up against Murray in the next round.
Murray was leading 6-5 in the first set against the world number 31 Benneteau when the Frenchman took a tumble, rolling his right ankle and landing badly.
"It looked like quite a bad one, he fell quite heavily," said Murray of Benneteau.
Grimacing in pain, Benneteau was patched up and tried to play on but gave up to end the abbreviated contest after 11 games.
"It was a tough match, a lot of long games, quite a few long rallies," said Murray.
"It was very cool conditions today in comparison to the other day, so the court was playing a bit slower. He was going for his shots and making it tough."