Nick Kyrgios has spoken of emerging from the "dark place" that threatened to engulf his tennis career following his controversial Australian Open loss to Andreas Seppi, his newfound enjoyment for the game manifesting in a second straight sets defeat of Novak Djokovic in the space of a fortnight.

Kyrgios said he had vowed to be more positive and less self-critical, starting on the practice court, and - after the 6-4, 7-6 (7-3) win over Djokovic that set up a Masters 1000 quarter-final against 18-time major winner Roger Federer in Indian Wells – also emphasised the importance of the recent return from injury of his girlfriend Ajla Tomljanovic.

Kyrgios says "something switched and now I'm really enjoying it again". Credit:Getty Images

​"I was in a pretty dark place. Even though I was at (No.)13 last year, but I wasn't in a good place mentally at all," the 21-year-old said. "I was beating myself down, and I just wasn't in a good place. Some of that's obviously having my girlfriend back on tour – it's going to be awesome seeing her every couple of weeks. Obviously, my mum (Nill) is here. I'm just trying to stay happy and just try and enjoy my tennis a little bit, you know."

Kyrgios admitted that towards the end of a 2016 season that ended with the infamous tanking episode in Shanghai, he was "just really dreading going to tournaments, didn't want to practice, didn't want to really do anything… I had a physical trainer for a little bit, but it was tough, because my team was motivated but I wasn't motivated.