Novak Djokovic admitted on Sunday he will miss injured rival Roger Federer as he prepares to begin his charge for the Dubai Championships.

The defending champion was forced to withdraw after this week undergoing right knee surgery which will reportedly keep the 20-time Grand Slam winner away until the summer grass season.

“It was a surprise, to be honest,” Djokovic said prior to his Monday start against Tunisian wildcard Malek Jaziri. “I knew he was struggling with an injury in the Australian Open. But no one knew really what was the injury, what is the extent of that injury.

“I really don’t like to see anybody going through surgery. I’ve been through that once, and hopefully the last time in my life.

“Roger is Roger – this sport needs him.”

World No 1 Djokovic last played here in 2016 and won his fourth Dubai title three years earlier. “I’m looking forward to competing again at the tournament where I’ve done well in the past,” Djokovic said.

“I’ve been coming here during the pre-season for at least seven to 10 days of training before I head to Australia. There’s also a very big Serbian community here so big support on the stands. Can’t wait to kick off.”

Seeded second after Djokovic is Stefanos Tsitsipas, who takes on Spain’s Pablo Carreno Busta after flying in straight from beating Canadian teen Felix Auger-Aliassime to the Marseille title.

Rotterdam winner Gael Monfils is seeded third and plays his first-round match on Monday against Hungarian Marton Fucsovics.