Andy Murray must ditch his temper tantrums and keep calm if he is to avoid an Australian Open upset against Canada's Milos Raonic, says former British number one Greg Rusedski.
Murray plays big-serving Raonic on Friday for a place in the final against Novak Djokovic and the Scot will be favourite, having beaten the world number 14 in their last two match-ups.
The Canadian's primary weapon is his serve. He has fired 84 aces, the second most in the tournament, and no player has won a higher percentage of points on their first serve, where he ranks at 83 per cent.
Murray is one of the best returners in the game and his counter-attacking style is often well suited to power merchants, whose movement can be sloppy and groundstrokes less reliable.
It does mean, however, that chances to break will be few and far between and Murray may need to keep his composure better than he has in previous rounds.
The world number two admitted off-court issues have been affecting his emotions on court, with his quarter-final win against David Ferrer particularly bad-tempered.
"I think he will clean that up and he needs to," Eurosport pundit Rusedski told Press Association Sport.
"He's been more talkative on court because of everything that's been stressing him out off the court, but when he gets down to business against Raonic he's going to have to keep calm.
"He's going to have to keep focus because the opportunities might be quite limited. They might be one or two in the set or in a tie-break - that's what it can be against the big servers.
"So he has to lift himself in the tough moments. He has to stay composed. He was immaculate against (Sam) Groth, another big server, and I expect him to be like that again."
Raonic is widely considered one of those capable of breaking into the elite of men's tennis and, after a season hampered by injury, the 25-year-old is much improved this year.
He beat Roger Federer en route to winning the Brisbane International this month and carried that momentum to Melbourne, where he has taken out French Open champion Stan Wawrinka in the fourth round.
"Milos is one of the best servers in the world," said Patrick Mouratoglou, the coach of Serena Williams.
"In this tournament he holds the second fastest serve at 234km an hour. But speed is far from the only thing about his serve. He has great accuracy and applies a lot of spin.
"But Murray is one of the best returners of the game and loves having a target at the net."
Murray will be making his 18th appearance in a grand slam semi-final and his fourth in five major tournaments.
The Briton endured a shock defeat to another big server, Kevin Anderson, in the US Open last 16 in September but the South African enjoyed an exceptional afternoon in which he served 25 aces and won 48 out of his 58 visits to the net.
"For me, Raonic has got to serve the match of his life against one of the best returners in the game at the moment," Rusedski said.
"He is dangerous but it comes down to Murray returning the serve well. If Murray returns the serve well, he's better in all categories.
"Once he gets the serve back and neutralises it, he's in the winning position straight off and also he passes so much better than, say, Wawrinka. who Raonic beat in the fourth round. I think Murray will do it in four sets."
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