Rafael Nadal has shown he was getting back to his best as he crushed Andy Murray at the World Tour Finals with an impressive 6-4 6-1 victory.

The Spanish fifth seed was dominant as the British world number two’s game fell apart in front of a home crowd at the 17,800-capacity O2 Arena in London.

“This is an important victory because that puts me in a good position to try to be in the semi-finals, and at the same time I have a big day against a great player on a tough surface,” Nadal said.

“When I don’t think about how to hit the ball, but when I think just about where to hit the ball, that’s good news.

“Today I feel free. I feel I’m enjoying it on court.”

World number four Stan Wawrinka of Switzerland takes on Spain’s seventh seed David Ferrer in Wednesday’s second match in the four-man group. Victory for Wawrinka, or for Ferrer in three sets, would ensure Nadal’s place in the semi-finals.

“He’s clearly playing better tennis now than a few months ago,” Murray said of the Spaniard.

“A lot of the players still felt, providing he stayed injury-free, that he would raise his game again and compete at the top of the game.

“He’s come back from tight situations which is signs he is getting back to where he wants to be.”

Both Nadal and two-time Grand Slam champion Murray are contesting their seventh Finals, the season-ending tournament disputed on a hard court between the year’s top eight players.

After an early exchange of breaks, Murray produced a pair of scissors from his bag and chopped off part of his fringe.

“I had some hair in my eye, and I just wanted to get rid of it,” he said.

In the second set, Murray made 16 unforced errors to Nadal’s three and won just 10 per cent of the points on his second serve as the Spaniard raced away with the match.

Murray will still be certain of finishing the season at number two, the highest year-end ranking of his career, if he beats Wawrinka in Friday’s final round of group stage matches, while Nadal faces compatriot Ferrer.