WATCH: Djokovic puts smile on young fan's face in Tokyo

Novak Djokovic had a great day back at the office in Japan on Tuesday. The world No. 1 ousted Alexei Popyrin 6-4, 6-2, in his Tokyo debut.

The Serbian brushed aside any worries hovering around his left shoulder injury which forced him to retire from the US Open fourth round against Stan Wawrinka. Before the 16-time Grand Slam champion left the court, he tossed his towel to a little boy in the stands, and the moment was captured on camera.

Djokovic will take on Go Soeda in the second round.