Djokovic off to a flier in London

NovakDjokovic

Three-time champion Djokovic will guarantee the end-of-year number-one ranking by winning all three of his Group A matches and laid down an ominous marker by taking just 56 minutes to secure victory at London's O2 Arena.

The routine success extended the Serbian's perfect record against Cilic to 11-0 and also stretched Djokovic's unbeaten run indoors, which began at this event two years ago, to 28 matches.

A healthy crowd in England's capital city may have been hoping for more of a contest after Stanislas Wawrinka had cantered to a 6-1 6-1 triumph of his own against an out-of-sorts Tomas Berdych in the day's first clash.

However, US Open winner Cilic – making his debut at the Finals - was simply unable to live with Djokovic, who was near his clinical best as he capitalised on the many opportunities that came his way.

The top seed – looking to become the first man to win the season-ending competition three years in a row since Ivan Lendl did so between 1985 and 1987 - started a little sluggishly and was twice taken to deuce in his first service game.

However, that was to be as good as it got for Cilic as Djokovic immediately lifted his level to reel off the subsequent six games and move a set to the good.

Two cross-court forehand passes in game five were among the highlights of the opener, which was wrapped up by Djokovic in 27 minutes.

Cilic briefly threatened to fight back after slipping 2-0 down in the second, breaking to love as his rival appeared to suffer a lapse in concentration.

Normal service was swiftly resumed, though, when Djokovic snatched yet another break to reclaim the initiative.

There was a growing sense of inevitability as the world number one charged towards the finish line by taking a sixth game on the serve of Cilic, who then provided a somewhat fitting finale by drilling a return into the net on the first match point he faced.

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