Djokovic had three weeks off due to a hamstring problem, after winning the Australian Open last monthNovak Djokovic impressed as he beat Tallon Griekspoor in straight sets to reach the Dubai Tennis Championships quarter-finals.
The 22-time Grand Slam champion, taken to three sets by qualifier Tomas Machac on Tuesday, beat the Dutchman 6-2 6-3.
"It's been a great evening for me," said Djokovic.
The Serbian world number one will face fifth seed Hubert Hurkacz or Pavel Kotov on Thursday for a place in the semis.
Djokovic is chasing a sixth Dubai title and is playing his first tournament since winning the Australian Open with a hamstring injury last month.
Defending champion Andrey Rublev saved five match points and recovered from a set down to advance.
The second seed beat Spaniard Alejandro Davdovich Fokina 1-6 7-6 (8-6) 7-6 (7-3) and will now face Botic van de Zandschulp of the Netherlands in the last eight on Thursday.
His hard fought win was in marked contrast to Djokovic, who recovered from a shaky first-round display to put in a ruthless display against Griekspoor.
"Yesterday, I really had to work hard to get a win," said Djokovic.
"Tonight, right from the beginning I was sharp. I played better quality tennis.
"Maybe the last three or four games were not the best to close the match, but I managed to find the good serve in the end."
