Perth, Australia, 30 December 2012 | AAP

Master coach Tony Roche is backing Bernard Tomic to deliver on his promise to make the world’s top 10 – so long as he finally knuckles down.

Roche, who delivered Tomic an infamous spray during this year’s Davis Cup loss to Germany, was among many impressed by the 20-year-old’s fight and spirit in his Hopman Cup comeback win on Saturday night.

Watching from Brisbane where he’s preparing Lleyton Hewitt for the Australian summer, Roche said Tomic’s 7-6(6) 3-6 7-5 victory over Tommy Haas in Perth showed the depth of the Gold Coaster’s talent.

“I thought he played well and I liked his attitude,” he said.

“What I saw in the first set, I was pretty impressed. I think everybody knows that if Bernard puts his mind to it and gets stuck in to training, he can be top 10. The ball’s pretty much in Bernard’s court.”

Tomic, who has slipped to 52 in the world rankings after peaking at No.27 in June, has been dismissed from Davis Cup duties to get his house in order.

Unperturbed, he’s already revealed his 2013 goal as an assault on the top 10.

While many have questioned the influence of Tomic’s father John as coach, Roche believes the 2011 Wimbledon quarterfinalist should be experienced enough to take the right advice.

“I would hope he takes it all on board and say ‘I’m at the age where I need to mature and let my racquet do the talking’,” he said.

“There’s no question he’s got the talent and he can do it.

“I hope he can continue to play (his unorthodox) way but maybe a little bit smarter.”

Despite Roche’s attack on Tomic during his listless 6-4 6-2 6-3 loss to German Florian Mayer in September, the Davis Cup mentor insists the pair get on well.

“I’ve got a lot of time for him,” he said. “He’s got a funny side to him. If he can put it all together, he’ll be a big star. There’s no doubt about that.

“It (the spray) may have appeared worse than what it was. Bernard, he was struggling playing the guy. He was just frustrated.

“I said `look mate, just get stuck into it’. He said `what’s the point?’. But we were fine. There was nothing in it really.

“I think we all forget he’s still very young. It’s all very new to him. He’s playing these hardened professionals. Sometimes it takes a little bit of time.

“But I have no doubt he’s going to make it.”