ATP World Tour Finals 2014: Hard life suits Novak Djokovic as he looks to continue hot streak It was only last month that Berdych confessed he had "never, ever experienced anything like that" after losing to Djokovic in the final of the China Open. The world No 1 won 6-0, 6-2 with a breath-taking display of attacking tennis, though the scoreline could have been even more emphatic. But for Berdych's bold return of serve when Djokovic had match point at 6-0, 5-0, the Serb would have become the first player in 46 years of Open tennis to "double-bagel" an opponent in a tour final. "I met somebody in the final who I've never seen before," a shell-shocked Berdych said afterwards. Djokovic, who described that performance as his greatest in a final, loves this time of year. The 27-year-old Serb's 47 career titles include 16 won in the last two and a half months of the season. He has won five China Opens (having won all 24 matches he has played at the tournament), three Paris Masters (including the last two years), two Shanghai Masters and three World Tour Finals - one of which in its previous guise of the Masters Cup. "There are some tournaments around the world that I play, like this one or Beijing, that I wish all the tournaments are played in one place, the way you feel on those courts," Djokovic said. Every player has his own preferred conditions where he loves to play - country, surface, so forth. But tennis is a unique sport. It's very demanding because it has a variety of different surfaces and conditions that affect the ball's bounce, humidity, so forth. All these different effects are factors that can influence the play. I've played very, very well the last couple of years in certain tournaments, including this one. That doesn't necessarily mean that I will play this way in some others, but I will try, no question about it. Consistency is always one of my top priorities because I know that with consistency and good health, I can give myself a chance of being No 1 of the world. Djokovic, who is attempting to win the title here for the third year in a row, underlined his position as the favourite with outstanding performances in his first two round-robin matches. He dropped a total of just five games in beating Marin Cilic and Stan Wawrinka, although he is still not certain of a place in the semi-finals. Cilic and Wawrinka meet in today's other group match with all four players still in with a chance of qualifying. "Nobody needs to tell me I need to win," Djokovic said. I know that already. That's what I try to do. That's why I'm here. I try to win every match I play. That's the kind of approach I will have. Djokovic has won Wimbledon twice and claimed nine clay-court titles, but hard courts have always been his favoured surface. He has also developed a remarkable record indoors. He will be seeking his 30th indoor victory in a row today, his last defeat having been against Sam Querrey in Paris more than two years ago. Asked if he liked indoor tournaments the best, Djokovic said: "It's hard to say. I like outdoor hard courts as well. I love playing on clay. The Wimbledon champion added with a smile: "Grass not too bad. But I've been very successful indoors over the last couple of years. Milos Raonic's debut in the World Tour Finals ended in disappointment on Thursday when a leg muscle injury forced him to withdraw shortly before his concluding round-robin match against Kei Nishikori. Raonic had still been in contention for a place in the semi-finals, despite losing his first two matches. The Canadian suffered the injury during his defeat to Andy Murray on Wednesday night and was advised that he could do further damage by playing. Read more: Nishikori beats substitute Ferrer Despite his withdrawal, Raonic said he had had "a great time" here after becoming the last player to secure his place in the field by reaching the final of the recent Paris Masters. "It's been a great experience, very different from the one I had last year as an alternate," he said. It motivates me a lot to come here next year, do what I can, do better than I did. I felt I did pretty well, but I always felt like I could do significantly better. David Ferrer, the first alternate, stepped into Raonic's shoes at late notice and made Nishikori work hard for a 4-6, 6-4, 6-1 victory. The result sent Federer through to tomorrow's semi-finals, whatever the result of his evening meeting with Murray, who went into the match knowing he had to win in straight sets to beat Nishikori to the other semi-final slot.