Andy Murray has described his win over Feliciano Lopez at the Australian Open earlier today as "a big step up".

The Scot's preparations for the Grand Slam in Melbourne had been hampered by a back injury that required surgery.

However, he was still able to overcome world number 28 Lopez 7-6 6-4 6-2 to book his place in round four, which maintained his 100% winning record against the Spaniard in the process.

"Today was a big step up for me," said the Wimbledon champion. "Feliciano is a top 30 player. He's a tricky opponent to play.

"I know I have a good record against him, but it doesn't change the fact he's not an easy guy to play against [and a] very different type of opponent to what you normally face. So it was a good test for me and I did well,"

Murray will now take on unseeded Stephane Robert for a place in the quarter-finals.