LONDON - Novak Djokovic demolished Holger Rune on Monday to reach the Wimbledon quarter-finals, staying on track for a record-breaking 25th Grand Slam as Taylor Fritz stunned fourth seed Alexander Zverev.

Ukraine's Elina Svitolina wore a black ribbon and broke down in tears as she progressed hours after a Russian missile barrage killed dozens and ripped open a children's hospital in Kyiv.

Seven-time champion Djokovic, who dropped sets in the second and third rounds, was expected to be tested by Rune, but instead gave the young Dane a harsh lesson, winning 6-3, 6-4, 6-2 in a shade over two hours.

The Serb, 37, still wearing a knee support on his right knee after surgery last month, did not drop a single point in the opening three games against his bewildered opponent.

He engineered a single break in the second set before two more breaks in the third set sealed a quarter-final against Australian ninth seed Alex de Minaur.

But despite his easy win, the Serbian launched an angry tirade against some sections of the Centre Court crowd, whom he accused of showing him disrespect.

"To all the fans that have had respect and stayed here tonight, I thank you from the bottom of my heart and I appreciate it," said a frustrated Djokovic after reaching a 60th Grand Slam quarter-final.

"And to all those people that have chosen to disrespect the player -- in this case me -- have a good night," he added, mocking his tormentors.

Djokovic seeking to equal Roger Federer's record of eight Wimbledon men's titles, is also aiming to pull clear of Margaret Court's mark of 24 majors.