Andy Murray insists he is unconcerned at dropping out of the world's top 20 after failing to get beyond the fourth round in the recent Masters Series events in America.

The British number one was defending a raft of ranking points after reaching the semi-finals in Miami last year and his early defeat has seen him plummet to number 22 in the world.

That is his lowest position for nearly two years but the Scot is confident the forthcoming clay court season will give him the chance to get back close to the top 10.

He insisted: "I missed the next four months last year because of injury so I haven't got any ranking points to defend and each week my ranking is going to move up for the next four months, so it doesn't really worry me too much."

As for his up-and-down season so far, Murray added: "It's been a bit inconsistent but I've won two tournaments and beaten Roger Federer, so it's been a good start in patches.

"Some of the matches haven't been good, I've lost a lot of close matches. But I'm happy with the way that it's gone, I just need to be a bit more consistent."

Murray will begin his clay court season at the Valencia Open next week.

"I missed the whole of the clay court season last year because of my wrist injury so I'm hoping I can get a good run this year and not have any problems with injury."

Murray spent most of his teenage years in Barcelona playing most of his tennis on clay.

"I practised on it a lot when I was younger and had good results on," he said.

"When I went over to practice in Barcelona I won some tournaments on the clay so it's a court I can play well on.

"But I've hardly played on clay for the last couple of years so I'm going to try and get some good practice in and try and get used to it again."

Murray has enlisted the help of two-time French Open finalist and former world number two Alex Corretja for the nine-week mini-season which ends at Roland Garros.

"I met him a couple of times last year, had lunch with him at one of the tournaments at the end of the year in Madrid and I thought he'd be a good guy to work with," Murray explained.

"Purely because I haven't played much on the clay lately and he's got a lot of experience and will teach me again how to do the things I used to do on the clay.

"It's the movement that's difficult, it's slippy under your feet, you slide into a lot of the shots and that's really different." 

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