Novak Djokovic became a serious Wimbledon title contender as he made his first semi-final since 2015 with a 6-3 3-6 6-2 6-2 win over Kei Nishikori.
It was performance of resilience and resolve from the former number one, reminiscent of the player who held all four Grand Slam titles two years ago.
After Djokovic took the first set, his Japanese opponent saved four break points before levelling.
The Serb took the next and fought from a break down in the fourth to win.
Djokovic told BBC Sport: "It feels great to be in the last four of a Slam. I've been building in the past couple of weeks. The level of tennis has been going up in the past couple of months and tournaments.
"This is not the first time I have been in the semi-finals here but I will try to enjoy this victory.
"I am very grateful to play on the court I love [Centre Court] and to be competing at a high level. I am trying to get in the best possible shape for the biggest possible events and it doesn't come much bigger that Wimbledon."
Djokovic's last run to the final four at Wimbledon ended with him winning the tournament - and he then went on to lift the 2015 US Open and 2016 Australian and French Open titles, becoming only the third man to hold all four Grand Slam trophies at the same time.
This is a 32nd Grand Slam semi-final appearance for Djokovic, although there was some doubt he would reach that mark.
A nagging elbow injury caused him to take an eight-month break from the sport prior to last year's US Open, and he also admitted to having to deal with personal issues.
He dropped out of the world's top 20 in May - yet his performance in June at Queen's, where he reached the final, suggested the 31-year-old could reach the second week at Wimbledon. But a semi-final?
After seeing off big servers Kyle Edmund and Karen Khachanov, he faced Nishikori, who had recovered from his own serious injury to hit peak form in reaching his first Wimbledon quarter-final.
On Centre Court, it was first blood to Djokovic and it seemed that his opponent would be for the taking. But then the Japanese player, world number four in March last year, survived those four break points early in the second set to level.
As Djokovic battled to find a way to victory, there then came a key moment.
The fifth game of the third set was almost a mirror of the third game of the second - which Nishikori had held despite three break points.
This time it was the Serb who saved three break points before he let out a huge roar when, with momentum on his side, he broke Nishikori in the next game.
Djokovic went on to take the set but there was to be another twist at the start of the fourth when the world number 28 - also known for his obdurate resistance - broke Djokovic again.
But instead of wilting, the Serb broke back immediately. This time there was nothing left in Nishikori's tank, although he leaves the All England Club having re-established himself as one of the leading contenders in Slams.
Djokovic, on the other hand, could face Rafael Nadal - a mouthwatering prospect - in Friday's semi-final.
Three-time Wimbledon champion John McEnroe
Novak looked great. That fire in the belly is back. Watch out if you've got to play this man. It was not a surprising result, but a pleasing one.
To see him play with that intensity and at that level is great. I don't know how you would break him and that's why it's exciting he is back in the mix.