Rafael Nadal produced a stunning performance to thrash Austrian fifth seed Dominic Thiem and reach a record 14th Monte Carlo Masters semi-final.
World number one Nadal, bidding for his 11th victory at the clay court event, won 6-0 6-2 in just 67 minutes.
Nadal, 31, will meet Bulgarian fourth seed Grigor Dimitrov in the last four.
Dimitrov reached his first Monte Carlo semi-final with a 6-4 7-6 (7-5) win over Belgium's David Goffin, who was leading 5-1 in the second set.
Croatian second seed Marin Cilic was beaten by Japan's Kei Nishikori, while German third seed Alexander Zverev beat Richard Gasquet in the last quarter-final.
King of Clay continues reign
Thiem, 24, was considered by many as Nadal's biggest threat in Monte Carlo, having beaten the Spaniard on his favoured clay surface in Rome last year and winning against Novak Djokovic to set up the quarter-final match.
However, the world number seven - aiming to become the first player to beat Djokovic and Nadal in the same clay-court tournament - was completely outclassed.
Nadal took the first set in just 31 minutes, winning four of his 11 break points and not facing one against his own serve.
Thiem avoided a double-bagel defeat by holding serve to trail 3-1 in the second set and was rewarded with a sympathetic ovation from the crowd.
But he failed to threaten Nadal's serve and the 16-time Grand Slam champion eased to an emphatic victory.
Nadal, who is aiming for a record-extending 11th French Open title when the tournament gets under way on 27 May, has now won 31 of his past 32 matches on clay.
"I think I played a great match - the best of the tournament," said Nadal.
"I played very aggressive, I knew I couldn't give Dominic time to hit the ball and I didn't."
Dimitrov edges past Goffin
Dimitrov and Goffin were playing for the first time since the Belgian suffered a freak eye injury during their match in Rotterdam earlier this year.
As a result 27-year-old Goffin is still wearing a special contact lens while playing, but it was his nerves which appeared to be the problem as he closed in on the second set.
Goffin failed to convert three set points on his own serve, tightening up as Dimitrov fought back to break twice to force a tie-break.
Dimitrov, ranked fifth in the world, clinched victory with his second match point as Goffin failed to avenge his defeat in the ATP World Tour finals last year.
Nishikori to face Zverev in other semi
Nishikori reached his first Masters 1,000 semi-final since July 2016 with a 6-4 6-7 (1-7) 6-3 victory over Australian Open finalist Cilic.
The 28-year-old, has dropped to 36th in the world after battling with a wrist injury over the past two years.
He failed to take two match points in the second set as Cilic overcame a knee problem to level, but won in the decider at the third attempt to stop the Croatian's fightback.
Nishikori will play Zverev in the last four after the third seed fought back against Gasquet to celebrate victory on his 21st birthday.
Gasquet was aiming to beat a second Zverev brother in two days after knocking out older sibling Mischa in the last 16 on Thursday, but the German won 4-6 6-2 7-5.