The world number one was a break down early in the first set, but eased to a 6-3 6-2 6-2 victory in a Tuesday night encounter on Rod Laver Arena.

Djokovic struck 42 winners and won 85 per cent of points behind his reliable first serve in a routine win as he eyes a third consecutive grand slam triumph.

The tournament favourite will face Jo-Wilfried Tsonga in the second round at Melbourne Park after dominating 231-ranked American Krueger.

Krueger has won only two tour-level matches in his career, but the 25-year-old looked undaunted on the big stage as he went a break up at 2-1.

That proved to be a false down, with Djokovic getting back on serve immediately with a couple of searing forehand winners and serving out the set after breaking again for a 5-3 lead.

Krueger earned a standing ovation from the crowd after winning an epic rally in the final game of the opening set, but he was broken again in the first game of the second following a rasping backhand winner from the 14-time grand slam champion.

There were flashes of brilliance from the rank outsider, Djokovic applauding a majestic forehand winner from his opponent, but the six-time Australian Open champion was dictating the contest and wrapped up the set with ease after going a double break up.

Krueger saved five break points in a marathon game to lead 2-1 in the third set, only for the relentless Serb to break in the Texas native's next service game.

Djokovic continued to pepper his tiring opponent with a barrage of powerful groundstrokes and went a double break up at 5-2, then served out the match to love.