New York, Aug 29: Novak Djokovic shrugged off a shoulder injury to beat Juan Ignacio Londero in the US Open second round while Roger Federer was tested by Damir Dzumhur before he progressed to the third round on Wednesday (August 29).

The world number one and defending champion needed treatment on his left shoulder during a 6-4 7-6 (7-3) 6-1 victory on Arthur Ashe Stadium.

Djokovic fell behind in the opening two sets before proving too good for Londero, maintaining his record of having never been eliminated before the third round at Flushing Meadows.

The 16-time grand slam champion will face either Dusan Lajovic or Denis Kudla in the third round.

Londero matched it with Djokovic from the baseline early and grabbed a surprise break in the fifth game when the Serbian challenged incorrectly mid-point.

However, he failed to consolidate, Djokovic – bothered by a left shoulder injury – needing six break points to get back on level terms.

Djokovic required treatment on his shoulder at 4-3 before taking the opening set, playing characteristically brilliant defence as Londero netted a forehand in the 10th game.

A double fault gifted Londero a break to begin the second set as he took a 3-0 lead on the back of winning 12 of the first 15 points.

However, Djokovic responded again, winning five consecutive games before needing a tie-break to claim the second set.

The pair traded breaks to begin the third before Djokovic powered away to win in two hours, 15 minutes.

Federer tested by Dzumhur

Federer had to come from a set down once again as he progressed into round three of the US Open with a 3-6 6-2 6-3 6-4 win over Damir Dzumhur.

Federer went behind to Sumit Nagal in his first-round match and suffered a similarly slow start in Wednesday's contest on Arthur Ashe Stadium.

But, much like in round one, the five-time Flushing Meadows champion - who made 45 unforced errors - found his form and once he nosed ahead in his 100th US Open match he never looked like slipping up.

The world number three was not handed it on a plate and although Dzumhur kept himself in it with some fine shots in the final set, Federer served out the win with the first match point on offer.

Dzumhur raced out of the blocks and stormed into a 4-0 lead after a second successive break.

Federer returned the favour in game five, but Dzumhur recovered from 30-0 down on his next service game - a sensational backhand slice forcing the former world number one to serve to stay in the set.

Federer did so successfully, but his opponent had his tail up and seized a one-set lead with just 29 minutes on the clock.

Another unforced error from the third seed handed Dzumhur a break point in the first game of set two, but the 27-year-old could not take his chance.

Federer made no such mistake, catching the Bosnian cold with a slick forehand down the line before executing a perfect drop shot en route to restoring parity.

A stunning cross-court backhand indicated Federer had hit his stride and the 38-year-old did well to save three break points for a 5-2 lead in the third.

With Dzumhur receiving treatment for an apparent side issue during changeovers, the Swiss closed out the set in his favour on his next serve.

Dzumhur's frustration at conceding his advantage started to show in set four, with a sloppy serve handing the 20-time grand slam champion a break in game three.

The finish line was in sight and Federer did not look back, finally breaking Dzumhur's resolve to set up a third-round clash with either Dan Evans or Lucas Pouille.

STATISTICAL BREAKDOWN Novak Djokovic [1] bt Juan Ignacio Londero 6-4 7-6 (7-3) 6-1

WINNERS/UNFORCED ERRORS Djokovic – 35/35 Londero – 24/43

ACES/DOUBLE FAULTS Djokovic – 7/8 Londero – 6/5

BREAK POINTS WON Djokovic – 8/17 Londero – 5/8

FIRST SERVE PERCENTAGE Djokovic – 51 Londero – 62

PERCENTAGE OF POINTS WON ON FIRST/SECOND SERVE Djokovic – 71/48 Londero – 49/46

TOTAL POINTS Djokovic – 102 Londero – 82

STATISTICAL BREAKDOWN Roger Federer [3] bt Damir Dzumhur 3-6 6-2 6-3 6-4

WINNERS/UNFORCED ERRORS Federer - 58/45 Dzumhur - 26/40

ACES/DOUBLE FAULTS Federer - 16/4 Dzumhur - 2/8

BREAK POINTS WON Federer - 5/9 Dzumhur - 2/8

FIRST SERVE PERCENTAGE Federer - 69 Dzumhur - 65