Novak Djokovic came through a bruising battle with seventh seed Andrey Rublev to maintain his bid for a record-equalling eighth Wimbledon men's title.
The Serb, also aiming to match Margaret Court's record of 24 major singles titles, fought back to win 4-6 6-1 6-4 6-3 in the quarter-finals.
Djokovic, 36, will play Italy's Jannik Sinner in the last four on Friday.
Sinner, 21, reached his first Grand Slam semi-final by beating Russian Roman Safiullin 6-4 3-6 6-2 6-2.
In contrast, second seed Djokovic will be contesting a 46th major semi-final - equalling Roger Federer's all-time men's record.
It is a repeat of their quarter-final last year when Sinner came close to beating Djokovic, before the veteran fought back from two sets down to win.
Four-time defending champion Djokovic's hard-fought win against Russia's Rublev was his 33rd consecutive victory at the All England Club.
He has not lost a completed match in SW19 since 2016 and has not been beaten on Centre Court since losing the 2013 final against Britain's Andy Murray.
"They are just numbers. In a tournament, I don't like to spend too much time thinking about statistics," said Djokovic.
"It is an active tournament, I'm still in it and all I'm thinking about is my next match.
"It is only going to get tougher, but I like the way I played."
