Tennis star and men's world No. 1 Novak Djokovic was at the center of controversy on Sunday after he accidentally struck a lineswoman with a ball at the US Open.

Djokovic smashed the ball towards the back wall after losing on serve late in the first set against Spaniard Pablo Carreno Busta, inadvertently hitting the lineswoman in the throat.

The Serbian star was subsequently defaulted from the tournament after a lengthy discussion with tournament officials, leaving the tennis world in shock.

Djokovic recently took to Instagram to explain his feelings, saying the incident has left him “really sad and empty.” Rather than show disdain at tournament officials for the default decision, Djokovic apologized to the lineswoman in question, also stating he hopes to this will be “a lesson for my growth and evolution as a player and human being.”

https://www.instagram.com/p/CE0AzAOH2cp/

Djokovic had previously lashed out in anger at losing a point just a few moments prior to striking the judge, which also likely factored into the default decision.

In any case, the overwhelming tournament favorite is out in a shocking turn of events.

“Nole” was hoping to capture his 18th career Grand Slam title in Flushing, Queens, as both Roger Federer (injury) and Rafael Nadal (health concerns) were absent from the men's field. Djokovic was also coming off a win at the Western & Southern Open, which was also held in Flushing the week prior.

Instead, Novak Djokovic will depart from the grounds with nothing but disappointment. That said, he made no excuses for his actions, which is notable considering his polarizing reputation in the sport.