ANDY MURRAY does not expect Novak Djokovic to be able to repeat his sensational 2011 next year.

The Serb goes into this week’s Barclays ATP World Tour Finals in London as the undisputed world number one, holder of three grand slam titles and having lost only four matches all season.

For a player who began the year looking to build on the solitary grand slam he won in Australia three years ago, it has been a remarkable achievement.

Assessing his friend’s prospects for 2012, Murray said: “How many times have players had pretty much the best year in tennis and then repeated it next year? It doesn’t happen in sports.

“Like Barcelona in football... they’re the best team, but to win back-to-back Champions Leagues, even though you’re the best, it’s so tough, the margins are so small.

“A lot of things have to go your way.”

Murray was an early victim of Djokovic’s annus mirabilis, the world number three being brutally outplayed in an Australian Open final from which he took months to recover.

He added: “I didn’t (match up to him) in Australia. I was disappointed with that match and I had to learn from that and realise why I didn’t that day.

“But other times I have played against him we always have a lot of long rallies, we have similar game styles and we both make a lot of returns. I feel like it is pretty even in a lot of respects. This year he has really carried it through.”