Novak Djokovic said Sunday that he hopes the clay courts at the Italian Open improve with use after what the tennis icon describes as an 'uneven' experience in the first two matches of his title defence.

The 22-time Grand Slam champion battled his way past Grigor Dimitrov to reach the last 16 in Rome, a tournament he has frequently described as one of his favourites.

However he expressed disappointment with the state of the centre court surface which he described as having "uneven, irregular bounces".

"What is interesting would be to understand how much tennis they're playing on the court actually before the tournament starts," Djokovic told reporters.

"If you don't use the court, and you have a clay court... the court breaks. You have many holes. You have an uneven surface, really bad bounces, a lot of clay. In Rome, it has been happening for quite a few years.

"Now there's really not much you can do. It's just kind of covering the holes here and there... Hopefully as the days pass and the tournament progresses, the court will get better."

Djokovic will face either Cameron Norrie or Marton Fucsovics in the fourth round.

td/dmc