Novak Djokovic crushed Marin Cilic 6-0, 6-3 on Friday to move into the semi-finals of the Monte Carlo Masters.

The world number one and top seed took just 65 minutes, winning the first eight games against Croatia's reigning US Open champion seeded eighth but still coming back from months of shoulder problems.

While Djokovic, who fired 15 winners and broke five times, will wait for a Saturday opponent from the Spanish pair of eight-times winner Rafael Nadal and fifth seed David Ferrer.

Gael Monfils continued into uncharted territory, with the Frenchman slugging Grigor Dimitrov 6-1, 6-3 for a career-first semi-final in the principality where he had never previously been past the third round.

The flamboyant Monfils followed up on his surprise victory against Roger Federer in the previous round while Bulgarian ninth seed Dimitrov came onto the clay as just a shadow of the player who knocked out holder Stan Wawrinka on Thursday with the loss of just three games.

"I'm just very happy," said Monfils. "For sure I'm surprised because this is not a period where I've played my best tennis so far.

"Hopefully tomorrow I'll be ready physically because I feel a bit tired. But should be fine, I hope."

Monfils said he followed a game plan to victory.

"I played deep and very heavy to show him that he needs to prepare the point. You cannot dictate the point on the baseline.

"I was very solid. The score doesn't show that, but it was a tough match. It was far from being easy. I'm tired now because I put a lot of intensity into it."

Monfils, levelling his career in Monaco to 8-8, will next take on Tomas Berdych, who advanced into the final four as opponent Milos Raonic retired with a right foot injury.

Monfils stands 1-5 against the sixth-seeded Czech, who won his 26th match of the season when Raonic quit.

Sixth seed Berdych, now 2-3 against Raonic, spent just 31 minutes on court against an opponent carrying the existing handicap into the match.

Berdych has yet to drop a set this week and was in total charge through his brief encounter with Raonic, striking 10 winners and breaking twice.

Berdych will be playing in his 18th semi-final at the Masters 1000 level; he also played Monte Carlo semis in 2007 (lost to Nadal) and 2012 (lost to Djokovic).

"I'm in the semi-final, which is good. It's positive to me," said Berdych, "But of course, it's not the ideal way that you want to finish the match."