US Open: Novak Djokovic overcomes shoulder complaint to book place in third round alongside Roger Federer

Djokovic received treatment for shoulder injury he has been carrying 'for quite a while now' before seeing off Londero 6-4, 7-6, 6-1

Novak Djokovic of Serbia in action against Juan Ignacio Londero of Argentina during their second round match at the US Open. AFP

Top seed Novak Djokovic of Serbia in action against Juan Ignacio Londero of Argentina during their second round match. EPA

Juan Ignacio Londero of Argentina celebrates a point against Novak Djokovic. EPA

Novak Djokovic struggled with a shoulder injury throughout his match with Juan Ignacio Londero. AFP

Damir Dzumhur of Bosnia and Herzegovina serves to Roger Federer of Switzerland. AFP

Novak Djokovic of Serbia is looked over by a trainer during a break in play. AFP

Damir Dzumhur a returns a shot during his second round match against Roger Federer. AFP

Novak Djokovic of Serbia celebrates winning the first set despite his hurt shoulder. AFP

Actor and singer Queen Latifah watches on at the USTA Billie Jean King National Tennis Center. AFP

Juan Ignacio Londero of Argentina returns a shot. AFP

Novak Djokovic returns a shot. EPA

Novak Djokovic of Serbia and Juan Ignacio Londero of Argentina meet at the net and shake hands after Djokovic won their match 6-4, 7-6, 6-1 to advance to the third round of the US Open. AFP

Roger Federer of Switzerland serves to Damir Dzumhur of Bosnia and Herzegovina during the second round of the men's 2019 US Open. AFP

Roger Federer returns a shot during his second round match against Damir Dzumhur. AFP

Roger Federer returns a shot against Damir Dzumhur. AFP

Roger Federer in action. AFP

Roger Federer eyes the ball as it passes the net. Reuters

Roger Federer applauds the crowd at Arthur Ashes Stadium after defeating Damir Dzumhur 3-6, 6-2, 6-3, 6-4. EPA

Roger Federer applauds the crowd at Arthur Ashes Stadium after defeating Damir Dzumhur 3-6, 6-2, 6-3, 6-4. EPA

Reigning champion Novak Djokovic battled a shoulder problem that hampered his serve and backhand as he secured a 6-4, 7-6, 6-1 win over Argentine Juan Ignacio Londero and reached the third round of the US Open.

Djokovic, who had work done on his left shoulder during his pre-match warm-up inside Arthur Ashe Stadium earlier in the day, was in clear distress when he took a medical timeout while leading 4-3 in the first set.

"I was definitely tested and this is something I have been carrying for quite a while now," Djokovic said when asked about the injury.

"It wasn't easy, obviously, playing with the pain but you have to find a way to fight and hope you get some lucky shots."

Djokovic returned to court to close out the first set and then had more treatment before Londero, playing in only his second main draw match at Flushing Meadows, broke him twice for a 3-0 lead in the second.

So bothered was Djokovic by his backhand that in the third game of the second set, at 30-30 and with Londero well out of position, he failed to get even a soft backhand to the open court over the net.

But he roared back to take the next five games, a stretch during which he managed to fire off a number of backhand winners, en route to strolling through the tiebreak before getting more treatment on his shoulder.

While Djokovic was nowhere near his best, Londero, who is in the midst of a breakout season that saw him win his first title, will be happy to have played at such a high level in his first career meeting with the Serbian.

Djokovic won't play again until Friday and until then, "I'll probably freeze my arm for 48 hours, not do anything with it and see what happens."

Up next for top seed, who has won four of the last five grand slams, will be either fellow Serbian Dusan Lajovic, the 27th seed, or American Denis Kudla, who were unable to play their match earlier because of inclement weather.

Roger Federer shook off another slow start to advance to the third round.

Federer, a 20-time grand slam winner seeking his first US Open crown since 2008, rallied to beat 99th-ranked Bosnian Damir Dzumhur 3-6, 6-2, 6-3, 6-4.

The 38-year-old Swiss third seed, who also dropped the first set against Indian qualifier Sumit Nagal in his opener, answered the wake-up call after conceding the first set with 17 unforced errors.

"When it happens like this, back-to-back matches, it's just a bit frustrating more than anything, especially when the level is that low and there is that many errors and the energy is not kind of there," Federer said. "But can only do better, which is a great thing moving forward.

"I didn't expect to hit 15 to 20 unforced errors, which is basically the entire set just sort of donated ... I clearly have to play better from the get-go."

Only 10 of 32 singles matches were played Wednesday as rain wiped out play except in enclosed stadiums, with Russian fifth seed Daniil Medvedev and three-time grand slam champion Stan Wawrinka among those postponed to Thursday.

"I definitely profit from everything I did in the game and my ranking to be put on center court on a day like this," Federer said.