World Tour Finals: Andy Murray on track to reach 'top level'

Murray has reached the semi-finals of the World Tour Finals three times

Britain's Andy Murray believes he is on course to get back among the elite competing for Grand Slam titles.

The world number six will face Japan's Kei Nishikori in Sunday's opening match of the ATP World Tour Finals

And Murray is hopeful his recent run of three titles in six weeks has put him in position to regain his "top level" and vie for major titles once again.

"The last few weeks have been good; I've started to make some improvements again and win more matches," he said.

"The big test is I want to be getting to the latter stages and competing for the Grand Slams. We'll only be able to test that next year really."

The Scot missed the season-ending championships in London last year after undergoing back surgery, and combined with the departure of coach Ivan Lendl in March, he slipped down the rankings.

However, the decision to commit to a punishing schedule of six consecutive weeks after the US Open saw Murray get back to winning ways.

"It was my idea," said Murray.

"I said to [coaches] Dani [Vallverdu] and Amelie [Mauresmo] after New York that I wanted to play tournaments, I wanted to try and play matches, and get back to winning matches.

"I told them I don't care if it's on the Futures [Tour], the Challengers, I want to get back to winning tournaments and having that feeling again."

Murray duly won three titles - his first since Wimbledon 2013 - and 20 matches as he battled back to claim a place in London.

Next in line is Nishikori, the world number five who made a huge breakthrough by beating Novak Djokovic to reach the US Open final in September.

Murray has a 3-0 record against the 24-year-old, making his ATP Finals debut, but they have not met since the early weeks of 2012.

"He's made big improvements this year in his game and in his ranking," said Murray.

Murray defeated Tommy Robredo in the Valencia Open final

"He's won a number of tournaments this year. He's played a lot of matches but also had quite a few injuries where he's missed periods of the year.

"But he's played some very good tennis this year; he's a young guy and he's going to keep getting better over the next few years."

Murray has been drawn alongside Nishikori, Milos Raonic and Roger Federer in Group B at the O2 Arena, with the match against Federer grabbing the attention.

For all his improvements in recent weeks, Murray has not beaten one of the top three - Djokovic, Federer or Rafael Nadal - in 2014.

"It's gradual steps and slow progress this year," he said.

"Hopefully just by playing against them and putting myself in position to compete against them, I'll get back to that top, top level again.

"I hope that it happens this week."