Novak Djokovic on Tuesday opened the defence of his U.S. Open title with a 6-3 5-7 6-2 6-1 win over Poland’s Jerzy Janowicz.
However, the laboured performance gave rise to fresh concerns about the world number one’s fitness.
After a sizzling start to the season that brought grand slam wins No.11 and 12 at the Australian and French Opens, Djokovic’s form has plummeted.
A third-round loss to Sam Querrey at Wimbledon was followed by a first-round exit at the Rio Olympics.
The Serb might have been in trouble on another day at Flushing Meadows but Janowicz has only advanced from the first round just once in four previous U.S. Open visits.
The player ranked 246 places below Djokovic looked unlikely to do it again on Tuesday.
Djokovic, a U.S. Open finalist five of the last six years, next faces Czech Jiri Vesely, a five-set winner over Indian qualifier Saketh Myneni.
The News Agency of Nigeria (NAN) reports that Djokovic arrived in New York having been hampered by a left wrist injury and distracted by undisclosed “private matters”.
But on Tuesday, trainers were called out early in the opening set to work on his right forearm.
Several times during the two hour, 37 minute match, Djokovic could be seen grimacing when hitting his powerful forehand, while his serve rarely looked threatening, stuck at around 100 mph.
“It was just prevention, it’s all good,’’ Djokovic told reporters.
“Look, each day presents us some kind of challenges that we need to accept and overcome.
“After all I’ve been through in the last couple of weeks it’s pleasing to finish the match and win it.’’
Up 3-2 in the opening set, Djokovic called for a medical time out during the changeover.
Janowicz took a seat in the stands while the world number one had his forearm massaged.
When play resumed, Djokovic immediately broke the Pole and held serve on way to taking the first set.
But in the second frame Djokovic’s discomfort became even more evident as he double faulted and then sent a wild forehand long as Janowicz broke to take control.
Normal service was resumed in the third and Djokovic moved in for the knockout punch, breaking Janowicz to open the fourth before wrapping up the match.(Reuters/NAN)