Tennis: Novak Djokovic sings for the US Open crowd

Serbian tennis star Novak Djokovic. Photo / AP

For whatever reason, no matter how many grand slams Novak Djokovic wins, he just doesn't seem to feel the love.

Not like Roger Federer and Rafael Nadal anyway. There's something intangible about that pair that makes everyone want to see them do well - whether it's the way they handle themselves off the court or the fact they've provided so many special moments on the court.

They've endeared themselves to sports fans everywhere.

Djokovic has won 12 majors and is far and away the best player in the world at present. He's admired, he's appreciated, he's respected and he's liked, but you get the sense he just isn't loved.

It's hard to pinpoint anything specific he has or hasn't done for such a result. He played the funny man earlier in his career when he'd imitate and mock certain players' habits in an effort to bring a bit of life into his matches, and while that earnt him fleeting laughs, long term love has eluded him.

He tried to change that on Tuesday afternoon (NZT) after his four-set win over Poland's Jerzy Janowicz.

The world No. 1 struggled to find any rhythm and was far from enjoying his time inside Arthur Ashe Stadium. That much was evident when he barely managed a smile after he'd sealed his win.

But he did manage to deflect attention away from his on-court woes with a strange moment during his post-match interview on the blue surface of Flushing Meadows.

Former Genesis frontman Phil Collins opened proceedings at the year's final major with a live performance of Easy Lover, and when the Serb was explaining how hard an act that was to follow, he broke out into a rendition of Genesis's I Can't Dance.

The crowd roared and applauded when the 29-year-old started singing and tried to pull off some dance moves - proof he had definitely won them over.

Djokovic endured a much more difficult opening to his US Open campaign this year than he would have been hoping for. He winced and grimaced his way though the match, struggling with a right arm that required treatment from a trainer after only five games.

Asked about his health during the on-court interview, Djokovic deflected the question, saying: "I don't think it's necessary to talk about this now. I'm through. I'm taking it day by day."

During the match, Djokovic hit first serves around 160km/h, sometimes slower - 40km/h or so below what's normal for him. He hit second serves in the 120km/h range.

He flexed that right arm, the one he has used to wield a racquet on the way to his 12 grand slam titles, and appeared generally unhappy.

In the stands, Djokovic's coach Boris Becker gnawed on his fingernails, looking nervous as can be.

This was the No. 1 ranked Djokovic's first match at a major tournament since losing to Sam Querrey in the third round of Wimbledon, which ended the Serb's bid for a calendar-year Grand Slam after titles at the Australian Open and French Open.

Heading into the US Open, Djokovic spoke about dealing with a left wrist injury that flared up in the days before the Rio Olympics this month.

But that appeared to be just fine against Janowicz, a former top-20 player who reached the semi-finals at Wimbledon in 2013 and is now ranked 247th after his own series of injury issues.

- With AP