Djokovic and Federer show class on opening day in London
Novak Djokovic and Roger Federer stamped their authority on the ATP World Tour Finals with straightforward victories on the opening day of play at London's O2 Arena.
Djokovic once again made a would-be rival look ordinary in a 65-minute 6-1 6-1 thrashing of Kei Nishikori, who later admitted he was "very ashamed" of the scoreline.
Life was tougher for Federer but he recovered from a poor start to defeat Tomas Berdych 6-4 6-2, with the Czech now having lost his opening match on each of the seven occasions he has qualified for the tournament.
Nishikori may have been embarrassed but he is in good company, with Djokovic now having won 23 matches in a row.
Indoors the world number one has not been beaten for three years and he is bidding to become the first player ever to win the title four years in a row.
The world number one oozed confidence as he talked about his display, saying: "I think I was at my best.
"Undoubtedly it's been an incredible performance that I was hoping I can have coming into the match, coming into this tournament where I've had a great record in the last couple of years.
"Reflecting back on those memories of course gives me more confidence, more comfort coming into every single match."
The O2 Arena paused for a minute's silence prior to the match to remember the victims of the Paris attacks on Friday, the court bathed in red, white and blue.
Federer and Djokovic will now meet tomorrow in a match likely to decide who wins Group Stan Smith, and tournament organisers will hope that it at least bucks the trend of one-sided singles clashes in the tournament.
That has not been the case in doubles, and on Sunday lunchtime Jamie Murray and Australian John Peers marked their debut at the tournament with a narrow 7-6 (7/5) 3-6 11-9 victory over Australian Open champions Fabio Fognini and Simone Bolelli.
It is the start of two huge weeks for Murray, culminating in the Davis Cup final between Great Britain and Belgium in Ghent.