Shanghai (AFP) - A new-look Novak Djokovic said he had given up on chasing Roger Federer's record 17 Grand Slam titles as he made a winning return to the tennis circuit on Tuesday.

Djokovic, the formerly indomitable Serb who has bullied his rivals over the past two seasons, said he had undergone a radical rethink after his travails of recent months.

The 29-year-old said he no longer saw protecting his world No. 1 ranking, now under threat from Andy Murray, as his priority, or breaking Federer's all-time record.

The 12-time Grand Slam winner beat Fabio Fognini 6-3, 6-3 at the Shanghai Masters in his first match back after skipping last week's China Open with an elbow injury.

"Right now, no," he said, when asked if surpassing Federer's 17 Major titles was still one of his goals. "I don't think about that at all.

"I don't think about any trophies or No. 1s in the world, rankings, anything like that. It's completely different. "

It is there, because I play partly because I enjoy being successful and seeing the results of my work. But on the other hand that comes second."

Djokovic has been in a funk since completing a career Grand Slam - and a run of four straight Major titles - at the French Open in June.

The Serb, who has admitted having "private issues", lost in Wimbledon's third round, and then failed to win a match at the Rio Olympics before finishing runner-up at the US Open.

He said he had had a complete change of heart about his approach to tennis because the "must-win mindset... is not working for me any more".

"I try to be in this moment and take things slowly, and, you know, I'm not rushing anywhere. I'm not in a need, you know, to achieve anything," he said. "I feel like I have overcome that step. Right now it's about just, you know, following my gut, following my instinct, whatever I feel like doing."