Novak Djokovic continued his good form, easing past Damir Dzumhur in the US Open first round on Monday.
After improving to 23-0 this year by winning the Western & Southern Open, Djokovic showed few signs of fatigue in a 6-1 6-4 6-1 victory over Dzumhur at Flushing Meadows.
The world number one endured a battle during the second set, but he closed out a win in one hour, 58 minutes.
Djokovic maintained his record of having never lost in the first round at the US Open, improving that record to 15-0.
The 17-time grand slam champion is the favourite to win his fourth US Open and he showed why early on Arthur Ashe Stadium.
Djokovic broke the Dzumhur serve twice and committed just six unforced errors to cruise through the opening set.
However, his level dropped and frustration grew as Dzumhur battled during a gruelling second set.
After the players exchanged breaks, there were long sixth and seven games, Dzumhur also squandering opportunities before Djokovic broke for 5-4, then sealing the set and letting out a huge scream.
An early break in the third set sent Djokovic on his way, with Dzumhur requiring treatment on his abdominal muscles as the Serbian closed out victory.
Djokovic will face Brit Kyle Edmund in the second round.
Djokovic  bt Dzumhur 6-1 6-4 6-1
Djokovic – 32/29
Dzumhur – 24/41
Djokovic – 5/5
Dzumhur – 2/8
BREAK POINTS WON
Djokovic – 7/19
Dzumhur – 1/7
FIRST SERVE PERCENTAGE
Djokovic – 60
Dzumhur – 56
PERCENTAGE OF POINTS WON ON FIRST/SECOND SERVE
Djokovic – 73/55
Dzumhur – 55/36
Djokovic – 105
Dzumhur – 72