Defending ATP Finals champion Novak Djokovic has pulled out of the season-ending event through injury, he said on Tuesday.

The record 24-times Grand Slam champion’s absence means that Norway’s Casper Ruud, Australian Alex de Minaur and Russian Andrey Rublev are all guaranteed to qualify for the eight-man event regardless of their results in tournaments this week.

“I was really looking forward to being there, but due to ongoing injury I won’t be playing next week,” the 37-year-old Djokovic posted on Instagram.

“Apologies to those who were planning to see me. Wishing all the players a great tournament. See you soon!”

De Minaur, who had been sweating on making the cut after losing to Holger Rune in the quarter-finals of the Paris Masters last week, will be making his debut in the event.

He will join world number one Jannik Sinner, twice former winner Alexander Zverev, four-times Grand Slam winner Carlos Alcaraz, former U.S. Open champion Daniil Medvedev and American Taylor Fritz. The ATP Finals run from Nov. 10-17.

Djokovic won a record seventh title at the season-ending tournament last year, beating Italian Sinner in the final.

He has not added to his Grand Slam collection this year and failed to win an ATP title, although he did claim his first Olympic gold medal by beating Spain’s Alcaraz in Paris.