Novak Djokovic moved a step closer to his first Monte Carlo Masters title since 2015 by beating Australian Alex de Minaur to reach the semi-finals.

World number one Djokovic, 36, edged a messy second set which saw seven breaks of serve to seal a 7-5 6-4 win.

The Serb is through to a men's record 77th semi-final at ATP 1000 events, surpassing Rafael Nadal.

Djokovic will play Norwegian eighth seed Casper Ruud or Frenchman Ugo Humbert for a place in the final.

Meanwhile, Italian second seed Jannik Sinner overcame Holger Rune 6-4 6-7 (6-8) 6-3 to set up a semi-final against Stefanos Tsitsipas.

Australian Open champion Sinner, 22, is the only player to reach the semi-finals at all three ATP Masters 1000 events this season, having won the Miami Open in March after losing to Carlos Alcaraz in the last-four at Indian Wells.

Greek 12th seed Tsitsipas, a two-time Monte Carlo champion, defeated Russian Karen Khachanov 6-4 6-2.

Djokovic admitted after his quarter-final win over Lorenzo Musetti on Thursday that he did not believe he was performing at his "top level".

But the 24-time Grand Slam champion is yet to lose a set on his way to his first Monte Carlo semi-final since he won the last of his two titles in 2015.

In moving past De Minaur, Djokovic, who turns 37 in May, became the tournament's oldest semi-finalist.