‘The big issue’ – Mischa Zverev unsure whether Novak Djokovic will ever recapture No. 1 spot

However, having missed the Australian Open and US Open, where he was defending champion and finalist respectively, and with no ranking points on offer at Wimbledon, where he was also defending champion, Djokovic has fallen to world No. 7.

And while Zverev is backing the 34-year-old to play for many years to come, he has placed doubt on his ability to get back to the top of the world rankings.

“The way Novak looks, he can play another three or four years,” Zverev told Eurosport in the Instagram live.

“Age is only a number if you do everything right on and off the court like Novak.

“But I don’t know if he will be world No. 1 again. The big issue will be: Will he play the Australian Open?

“If it goes badly and later in the year there are no ranking points at Wimbledon again, he would potentially be 4000 points short.”

The win in Tel Aviv moved Djokovic to a 28-6 win-loss record for the season, and represents his third win of the season after Wimbledon and Rome.

“My approach is to win tournaments wherever I am and I’m glad that I have a team of people around me that makes sure that I am in the best shape in order to be a contender to win titles,” Djokovic said after the win in Tel Aviv.

“That’s why I came to Israel, to try to win the title. First time playing here [since a] Davis Cup tie more than 15 years ago, so it was a really amazing experience.

“I played some very good tennis, I think. I [didn’t] drop a set the entire week. I hadn’t played a tournament in three months, so it was really extra motivation for me to really do well, particularly because people have been so friendly and so supportive of me throughout the week.

“I’m taking some great confidence into next week as well. Just everything really that we experienced this week was positive.

“The way people treated us when we landed in Israel all the way to the last moments now of our stay here has been truly wonderful and I am very grateful because it was more than a tournament for me.

“It was great connections that we established with people, all of us in the team, that we will cherish and will give us positive emotions for what’s coming up.”