Novak Djokovic's mental strength makes him stand out from most of his rivals on the ATP Tour, according to 11-time grand slam singles champion Rod Laver.
Djokovic endured a difficult end to 2016 as his form dipped for the first time in many years, the Serbian eventually losing the world number one spot to Andy Murray.
After winning the French Open to complete a career grand slam in June, the 29-year-old was dumped out of Wimbledon in third round and was a first-round casualty at Rio 2016.
He recovered his form to reach the final of the US Open but was beaten by Stan Wawrinka, and he could not win the ATP World Tour Finals either as Murray got the better of his rival in London.
While those setbacks could affect some players, Laver believes Djokovic will go into the Australian Open confident in his own game, something which makes him unique.
"He plays so well ... he's so consistent with his game," Laver told Omnisport.
"His groundstrokes, he out-rallies all of the players. If he needs to play a match and just keep the match in play, he can pull it off and he's prepared to put the time in to win the match.
"A lot of players say I'm gonna change, I'm gonna serve and volley and get a shorter match. He stays with his own game and that's probably his asset."
Djokovic could win a seventh Australian Open title in Melbourne this month, something Laver admits he did not expect to be possible when he first saw the Serbian in action.
He added: "[It is a] huge situation to be able to [win seven], I think I saw his first match which he won and he was battling to play.
"I don't know if it was even five sets but he was having trouble with his lungs, his fitness and he realised I've got to do something about this so he went on a gluten-free diet, he went on a fitness programme, a stretching programme and here he is.
"He started off barely winning the first Australian and now he's been winning them pretty comfortably and playing the best players in the world."