Abu Dhabi - Former world No 1 and 12-time Grand Slam title winner Novak Djokovic will be more dangerous than ever when he makes his long-awaited return from an elbow injury, top 10 rival Dominic Thiem said on Wednesday.
Djokovic hasn't played since retiring from his quarter-final at Wimbledon against Tomas Berdych in July, but the 30-year-old makes his comeback at the Mubadala World Tennis Championship in Abu Dhabi on Friday before launching his competitive campaign as top seed at the Qatar Open next week.
"We all know what Djokovic is capable of," said Austria's Thiem who is also playing in the six-man Abu Dhabi field.
"But now, if his injury is fine, he's probably more dangerous and better if he had some time to recharge. I think everybody wants to know how he's playing again and we'll see his first matches here."
Thiem feels Djokovic could make the same impact as Roger Federer and Rafael Nadal who came back from injuries this year.
Federer won the Australian Open and a record eighth Wimbledon while Nadal claimed a 10th French Open and the US Open in a Slam sweep for the two veteran stars.
Nadal and Federer also ended the year at one and two in the world.
"I think we can expect the same from Djokovic because he is in the same league as Roger and Rafa. He is also one of the greatest players of all time," added Thiem who claimed his first ever win in six meetings over Djokovic at the French Open quarter-finals in June.
"It's going to be an exciting year. There are players returning from injuries, but apart from Novak, nobody else will make a comeback like Roger and Rafa.
"It's too tough. I think everybody can look forward to a great and tense start of the season."
Also back in action in the exhibition tournament, which starts at the Zayed Tennis Centre in the UAE capital from Thursday, is former women's number one Serena Williams.
The 36-year-old American was last seen in action winning the Australian Open for a modern-era record 23rd Grand Slam title in January.
She then took a sabbatical to give birth to her first child, Alexis Olympia, in September.
Williams takes on reigning French Open champion Jelena Ostapenko in a match scheduled just before the men's final in Abu Dhabi on Saturday evening.
Another player in the field looking to build on his successful 2017 is South African Kevin Anderson.
The world number 15, who reached the final of the US Open before losing to Nadal, also welcomed the return of Djokovic and Williams.
"It is dubbed an 'exhibition', but the tennis this week in Abu Dhabi is great - it is very competitive and everyone is going to give it their all. So, it would be a good way to return for both these players," said Anderson.
"I think it is great. We all are eager to see what Novak is going to do when he comes back. And I heard just yesterday that Serena is coming here, so it is obviously very exciting for the tournament.
"Serena is the greatest women's tennis player of all time, and perhaps the greatest competitor - man or woman - that I have seen. It has been a long break for her, but I am sure she will come back more determined than before to succeed."
The men's field in Abu Dhabi features US Open semi-finalist Pablo Carreno Busta, Spain's Roberto Bautista Agut and 20-year-old Russian Andrey Rublev apart from Djokovic, Thiem and Anderson.
Djokovic and Thiem have byes to the semi-finals.
Nadal and three-time major winner Stan Wawrinka were scheduled to take part but pulled out to allow further recuperation from respective knee problems.