Novak Djokovic opened his season with a 6-2, 6-2 win over German qualifier Dustin Brown on Monday at the Qatar Open.
The top-ranked Serb avoided the post-season exhibitions last month after an exhausting 2015 season in which he won three major titles and reached the final in the other.
The Qatar Open was the only tournament in 16 played in 2015 in which Djokovic failed to reach the final, instead losing in the quarterfinals.
Last year, Djokovic won a career-best 11 titles and finished with an 82-6 record.
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