Tennis supercoach Darren Cahill has urged Bernard Tomic to bring more intensity to the practice court in his ongoing bid to bridge the gap on the grand slam giants.

Two-time major winner Andy Murray dealt Tomic another yet another sobering reality check with his 6-4 6-4 7-6 (7-4) fourth-round Australian Open defeat of the last local standing at Melbourne Park.

It was the seventh time that either Murray, Novak Djokovic, Roger Federer or Rafael Nadal had been a mid-round roadblock for Tomic at a grand slam.

Tomic has also fallen on seven other occasions to top-15 rivals at the four biggest annual events, highlighting the enormity of the challenge he faces to make good on his promise to crack the world’s top 10.

Cahill, who helped Lleyton Hewitt become the youngest-ever year-ending men’s No.1 and then Andre Agassi the oldest, would like to see a more energised Tomic – and says that starts at training.

Cahill made the interesting observation during Tomic’s latest loss to Murray that the reason the Australian No.1 always looked like he was playing at 50 per cent was because his father had put him through endless practise sessions all his life.

“The only way he can get through them is by conserving energy,” Cahill said from the ESPN commentary box.

“He’s on the court for four or five hours every day. It’s impossible … he doesn’t know a hundred per cent.”

Cahill wasn’t suggesting Tomic doesn’t give his all, merely that his famously laconic playing style was a by-product of the relentless sessions.

Cahill said he’d prefer to see Tomic, now coachless but being mentored by Davis Cup captain Hewitt, have “shorter, sharper” workouts to simulate match conditions.

Tomic, who will slip from a career-high No.17 to 20th in the rankings next week, maintains he’s on the right track and will “absolutely” reach a point where he’s comfortable competing with the heavyweights of men’s tennis.

“Novak is one in the world and Andy is two. That’s the reason they’ve won so many grand slams,” he said.

“They’re the best in the world. There’s no better than them now.

“I need to get a little bit fitter.

“I know what it takes to get there. I’m going to work as hard as I can.”

While Murray continued his domination of Tomic with a fourth straight-set win in as many meetings, the Scot said criticism of the 23-year-old had been harsh.

“Obviously if he can start getting a few more wins against the top players, that would help. But it seems like he gets a bit of a hard time,” Murray said.

“I think he’s the youngest player in the top 20. Most years he makes improvements. He’s the No.1 player in Australia.

“On the court, his personality is very different to someone like a (Nick) Kyrgios. But he deals with pressure well.

“He plays good tennis at the Aussie Open. He’s performed extremely well in Davis Cup. I think he’s only lost two or three Davis Cup matches.

“Obviously if he can be consistent throughout the year, it’s normal for young players to have ups and downs.

“But he seems to be playing more consistent tennis. He’ll definitely keep moving up the rankings.”