BELGRADE, Serbia (AP) — Novak Djokovic won’t defend his ATP Finals title after ruling himself out on Tuesday due to an unspecified injury. Djokovic wrote in an Instagram story, “I was really looking forward to being there, but due to ongoing injury I won’t be playing next week. Apologies to those who were planning to see me.”

Jannik Sinner, Alexander Zverev, Carlos Alcaraz, Daniil Medvedev and Taylor Fritz had already qualified before Djokovic’s announcement

Djokovic had qualified automatically for the ATP Finals but his withdrawal means Alex De Minaur and Andrey Rublev are confirmed for the eight-player tournament in Turin. They join Jannik Sinner, Alcaraz, Alexander Zverev, Daniil Medvedev, Taylor Fritz and Casper Ruud.

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,

Defending champion Novak Djokovic pulls out of the ATP Finals because of injury, a move which sets the eight-man field for the event.

Citing an "ongoing injury," Novak Djokovic announces his withdrawal from the season-ending ATP Finals on Tuesday.

Earlier this year, the 37-year-old said he plans to prioritize majors and country-based tournaments for the rest of his career.