Roger Federer faced serious questions over his future on Wednesday after crashing out of Wimbledon in the quarter-finals, just five weeks shy of his 40th birthday.
Eight-time Wimbledon champion and 20-time Grand Slam title winner Federer lost 6-3, 7-6 (7/4), 6-0 to a Poland's Hubert Hurkacz, a player 15 years his junior.
There were no such problems for world number one and five-time champion Novak Djokovic who reached his 10th Wimbledon semi-final and 41st at the Grand Slams.
Djokovic, looking to equal Federer and Rafael Nadal on 20 majors, defeated Hungary's Marton Fucsovics 6-3, 6-4, 6-4.
He will face Canada's 10th seed Denis Shapovalov, who beat Russia's Karen Khachanov 6-4, 3-6, 5-7, 6-1, 6-4, for a place in Sunday's final.
Hurkacz will tackle Italy's Matteo Berrettini in the other semi-final.
Defeat was only Federer's 14th at Wimbledon in 119 matches and his first straight-sets loss since an opening round exit against Mario Ancic in 2002.
It was also the first time he had lost a set 6-0 at Wimbledon.
"I really don't know. I've got to regroup," said Federer when asked if his Wimbledon career was over.
"With everything that comes after Wimbledon, we were always going to sit down and talk about it. I got to take a few days”
"Just see, okay, what do I need to do to get in better shape so I can be more competitive."
Those discussions will also centre on his participation in the Olympic Games in Tokyo which start in just over two weeks' time.
"Clearly there's still a lot of things missing in my game that maybe 10, 15, 20 years ago were very simple and very normal for me," Federer added ruefully.
World number 18 Hurkacz had never got beyond the third round of a Grand Slam before this Wimbledon.
However, boosted by having defeated world number two Daniil Medvedev in five sets in the last 16, he was a break up on a sluggish-looking Federer in the sixth game of the opening set.
The Swiss star, who underwent two knee surgeries in 2020 and was bidding to be the oldest man in the Wimbledon last-four in over a half a century, carved out a break for 2-0 in the second set.
He couldn't hang on and Hurkacz levelled in the seventh game from 1-4 down before dominating the tiebreak.
Federer looked punch-drunk and he was quickly down 0-2 in the third set before Hurkacz wrapped up the decider in just 29 minutes in front of a stunned Centre Court.
He is only the second Polish man to reach the semi-finals at Wimbledon -- Jerzy Janowicz being the other in 2013.
"It's super special to have played Roger here, it's a dream come true," said Hurkacz.
Victory for Djokovic was his 100th on a grass court.
Djokovic became only the third man to capture all four majors more than once with his second French Open victory last month.
Now he is halfway to becoming the first man in the Open Era and only the third in history to complete a calendar Grand Slam of all four majors.
"Sometimes things do look surreal for me but I try to live in the moment and take every opportunity I have on the court," said Djokovic.
"Going for history is a huge inspiration for me, let's keep it going."
Djokovic raced into a 5-0 lead in the first set before 29-year-old Fucsovics got on the board.
The world number 48, bidding to become the first Hungarian man since 1948 to make the semi-finals at Wimbledon, saved five set points.
However, the rearguard action was too late to prevent the champion edging ahead.
The top seed broke for the only time in the second set in the ninth game which was enough for a two sets lead.
Djokovic had spent three hours fewer than the muscular Fucsovics in getting to the last-eight and his freshness showed when he crucially broke in the first game of the third set and then fought off two break points in the sixth.
Shapovalov fired 17 aces and 59 winners past Khachanov to reach his first Grand Slam semi-final.
The left-handed Canadian will be a huge underdog against Djokovic having lost all six matches against the world number one.
"Obviously he's the best player in the world but I think anything is possible. When you look at the scoreboard first thing it will be 0-0," said the 22-year-old.
Berrettini defeated close friend Felix Augier-Aliassime 6-3, 5-7, 7-5, 6-3 to reach the semi-finals for the first time.
The 25-year-old is only the second Italian to reach the last four after Nicola Pietrangeli in 1960.