Andy Murray may not appear at ATP World Tour Finals at the O2 Arena after dropping out of the top 10 for the first time since 2008

Scot missing from the tournament would be a major blow for fans

Andy Murray in action at the US Open (GETTY IMAGES)

Andy Murray could miss the ATP World Tour Finals at The O2 Arena in London after he dropped out of the Top 10 rankings for the first time since 2008.

Marin Cilic's win at the US Open has pushed the Scot down to No 11 in the world meaning he is no longer a sure thing to play in the popular London tournament tat takes place from 9-16 November.

Murray, 27, lost to Novak Djokovic in the quarter-finals in New York and now has a significant number of points to make the World Tour Finals; the tournament features the top eight players in the world.

Tomas Berdych currently occupies the final spot but Murray will have to battle with Milos Raonic and Grigor Dimitrov, all of whom are within 400 points of each other, to make the tournament.

Murray has three events between now and November and to be in with a chance of playing he may need to reach the final at either the Shanghai or Paris Masters.

Murray was ranked as high as No 3 in September 2013, two months after winning Wimbledon, but has suffered with loss of form after undergoing back surgery.

Since then, his win against Jo-Wilfried Tsonga in round four of the US Open is the only time he's beaten a top 10 player; he only managed the quarter-finals at the Australian Open and Wimbledon and was beaten in the semi-final at the French Open.

Murray, along with Novak Djokovic, Rafael Nadal and Roger Federer who have all qualified, is the biggest draw for the Barclays-sponsored event and his face is plastered across most of the promotional content.

It remains to be seen how Murray's absence will affect ticket sales for the event.