Andy Murray
Andy Murray has dropped to world number 156 having not played for almost a year. In this picture, Britain's Murray plays a double-handed backhand during practice, ahead of his first round match at the ATP Queen's Club Championships tennis tournament in west London, June 18, 2018 GLYN KIRK/AFP/Getty Images

Novak Djokovic warned Andy Murray about the mental challenge he faces as he prepares to make his comeback after spending almost a year out due to a hip injury.

The Scot’s last competitive match was his loss at Wimbledon in the quarterfinals in 2017 and he has since undergone surgery to repair the hip injury that has troubled him since the start of last season.

Murray will make his comeback against Nick Kyrgios at the Fever-Tree Championships in London on Tuesday. The former world number one is hoping to use the Queen’s Club tournament to gain match fitness ahead of the Wimbledon Championships that gets underway in July.

The 31-year-old admitted being out with an injury and requiring surgery was the lowest point of his career thus far and is glad he is able to make a comeback. Murray made it clear he is not returning with the intention of winning Wimbledon or returning to number one in the world, but to just get back to playing regularly on the ATP Tour.

Djokovic is no stranger to lengthy injury absences as the Serbian is himself coming back from a six month stint on the sidelines due to an elbow injury. He returned at the start of the year, but had to undergo a minor procedure after the Australian Open in January.

The former world number one returned in March for the BNP Paribas Open and has since played regularly on the tour. Djokovic’s best result this season was the semi-final appearance at the Italian Open, as he too is still trying to recapture his old form that took him to 12 men’s singles Grand Slam titles.

Djokovic warned Murray his biggest challenge to overcome when he makes his comeback will be mental rather than physical. He is certain it will take time for the Scot to completely convince himself he is over the injury and can play without any fear of a relapse.

"I think the biggest challenge will always be mental," Djokovic said, as quoted on Tennis World USA. "How to get it out of your head, understand that it's behind you, that you're fine now, that you're healthy and you can focus on your game rather than thinking 50 percent of the time about whether or not something can happen."

Djokovic, however, is delighted to see Murray back on the court and admitted he does not like to see any tennis player miss out through injury. The duo have enjoyed a long-standing rivalry and were the two best players on the ATP Tour in 2016.

“I wouldn’t want to see any player injured,” Djokovic said, as quoted by the Express. “That’s not allowing you to have a fair competitive field and level of competition and have an opportunity to do what you do best. ... I have known him since I was 12 years old and I have always had a wonderful relationship with Andy. We are still big rivals on the court and we have had so many great matches but he deserves a chance to come back.”