Novak Djokovic has dismissed claims from his former coach that he is suffering from a number of "personal problems".

Having won three Grand Slam titles last year, the Serbian has only managed to emerge victorious from the Australian Open so far in 2012.

Such statistics have seen his first ever mentor, Jelena Gencic, question Djokovic's current mental state heading into the US Open.

However, the 25-year-old has insisted that he has nothing on his mind to complain about.

"I'm sure she didn't mean any harm. Everybody has problems," Djokovic said. "My problems are much smaller than an average person's problems. I cannot complain about my life."

Djokovic will be the defending champion at Flushing Meadows.