Novak Djokovic is not going through a bad patch and is still the best player in the world, according to Shamil Tarpischev.

The previous world number one dropped to number two in the rankings at the end of 2016 following an early exit in Wimbledon, a finals loss to Stan Wawrinka in the US Open and defeats in Shanghai and Paris.

The Serbian's misery continued at the 2017 Australian Open where he crashed out in the second round of the tournament to Denis Istomin – the first time that Djokovic failed to reach the quarterfinals in Melbourne as well as the first time he had lost to player ranked outside the top 100 in a Grand Slam.

Russian tennis federation president Tarpischev – who saw his team lose to Djokovic's Serbia in the Davis Cup – believes the 29-year-old is still the best tennis player in the world despite Andy Murray currently being atop the rankings.

"I'm not [in] agreement with who thinks Djokovic is going through a bad moment," Tarpischev said as quoted on Tennis World USA. "For me Novak is still the world no. 1. He has many abilities than other players that allow him to be ahead of them."

"If he moves quickly again and comes back to be physically like he was, I think that in a few months he will be at his best level."

Tarpischev also believes Djokovic could benefit from a lighter schedule – something that many tennis stars have cited recently.

"I think he shouldn't play too many events, he should choose carefully the tournaments to play," he added. "I don't know how he trains and what happens in his practice sessions, but I think he should be very careful when it comes to choose his calendar."

Djokovic has been suffering from an ongoing issue with his shoulder, most recently in the Davis Cup, while he has also suffered from personal problems. Tarpischev believes when the reigning French Open champion is fully focused, he is usually hard to stop.

"When he enters an event with the goal to win it, he does it," he explained. "If instead he has some issues, an injury or something mentally, he struggles."

Tarpischev was also asked about Maria Sharapova, who is returning to the sport after her doping ban and whether she and Djokovic can become world number ones again.

"Maria won't definitely (be able) do it," he added. "It will take much time to be able to comeback to the top. Djokovic can definitely do it. He has everything to achieve it."