"It's not the way you want to win a match, especially against one of your best friends," Djokovic said.
The 2008 champion will next play Nicolas Almagro or Ivan Ljubicic.
Djokovic did not fail to reach the quarter-finals in all four Grand Slams last year and will be pushing the top two seeds Rafael Nadal and Roger Federer for glory in Melbourne this time round.
The 29th-seeded Troicki suffered breaks of serve against Djokovic in the second, fourth and eight games to lose the opener on Friday on Hisense Arena.
Troicki, who racked up 17 unforced errors, had already called for the trainer at the third changeover and did not receive treatment on the court initially before deciding after eight games he was unable to continue.
Next Djokovic will get Almagro who beat Ljubicic in 3 sets but never the less it should be another easy win for Djokovic. it`s getting interesting.!!!!!
