The match in Melbourne lasted only 52 minutes as Nishikori was forced to retire injured in the second set.

At that stage, the five-time champion, Djokovic, was leading the game 6-1, 4-1. Following the match, Djokovic expressed his disappointment in how it ended.

“I love to battle, especially against Kei,” said Djokovic, through to the 34th Grand Slam semi-final of his career.

“We’ve played so many matches throughout our careers, especially here a couple of times years ago. I hope he can recover, and it’s not something very serious.”

The 13-time Grand Slam champion, Djokovic, added that Nishikori’s retirement was a blessing in disguise.

“As they say, this is exactly what the doctor ordered for me after that match two nights ago, not to spend too much time on the court,” Djokovic said.

“I’ve had plenty of matches this year already. Now I’m in another semi-final, and I’ll do everything to get ready for that one.”

Djokovic will next face Lucas Pouille who beat Milos Raonic 7-6, 6-3, 6-7, 6-4.

In the woman’s quarter-finals, Naomi Osaka beat Elina Svitolina 6-4, 6-1, and Karolina Pliskova beat Serena Williams 6-4, 4-6, 7-5.

@MorganPiek OFM Sport