Three-time Wimbledon champion John McEnroe has told Andy Murray he can win a "few more" Grand Slam titles - if he puts greater faith in his volleying.

Murray was due to play Australia's talented 20-year-old Nick Kyrgios for a place in the French Open last 16 this morning as he bids to add a first Paris crown to the US Open and Wimbledon titles he won in 2012 and 2013.

The Scot has enjoyed his best-ever clay-court season so far, winning 10 consecutive matches on the red sand, and his success has in part been due to a more aggressive style of play.

Drop-shots, volleys and a more potent second serve have all helped Murray become less predictable and McEnroe, who is considered one of the greatest-ever net players in the history of the game, believes the British number one should go even further.

"We obviously play totally different games but the similarity is the hands," said McEnroe, who is providing analysis for British Eurosport's live French Open coverage.

"I think he has a beautiful feel for the ball and that's what I was lucky enough to be taught - to mix it up.

"He is a bigger guy, he hits a bigger ball off the baseline. I actually think he would be better off coming forward more because he could use the hands to his advantage.

"The skills that he hasn't shown a lot are the ones at the net.

"If he did that more frequently that would help him win at least a few more majors.

"It may not show so much at the French Open, but I think it would show at Wimbledon and the hard court events.

"You see Roger Federer doing it now, coming in, being more aggressive, I think Andy needs to do that also."

Murray is seeded third at Roland Garros and will likely have to beat either world number one Novak Djokovic or nine-time French Open champion Rafael Nadal even to reach the final.

The 28-year-old can take heart, however, from recent form which has seen him take a maiden clay-court title in Munich last month, before beating Nadal for the first time in Madrid.

"Belief is probably the biggest thing, this is probably the first year that he thinks he can win," McEnroe said.

"Beating Rafael Nadal finally in Madrid is huge for him.

"He is doing a lot of things that a lot of people have implored him to do in the past - whether it's taking the ball early, being more aggressive, taking control of points.

"But he has always been able to play on clay - he played in Spain as a young kid, he's been in the semis of the French a couple of times.

"People always knew he could do it but I think he really believes he can go all the way now - that's the biggest difference for me."

Murray was made to work hard for a 6-2, 4-6, 6-4, 6-1 victory over Portugal's Joao Sousa on Thursday but Kyrgios will provide a much sterner test.

Kyrgios lost to Murray in straight sets at the Australian Open quarter-final in January but has proven himself a dangerous opponent, having beaten Nadal at Wimbledon last year and Federer only three weeks ago in Madrid.

"He's obviously a very talented guy," Murray said.

"He likes the big stage. He's had some good results at the slams.

"Also away from the slams, he beat Roger a few weeks ago on the clay, so he can cause a lot of players trouble.

"He's an exciting guy to watch and he's going to be around for a long time, I'm sure."