While China's Li Na famously says she only has to listen to her husband and coach Jiang Shan one hour a day, her fitness trainer Alex Stober has never had any problems getting through to the French Open champion.
The world number six cruised into the second round of the Australian Open on Monday with a routine 6-3 6-1 win over Uzbekistan's Ksenia Pervak in stifling heat at Melbourne Park.
German Stober, who whipped Pete Sampras and Andre Agassi into shape during their careers, said that while Li can get a little fiesty with her husband, her dedication to her tennis career is without question.
"I can tell you Li is incredibly easy to work with, she's incredibly disciplined, she's a hard worker," he told Reuters.
"She would never question whatever you are telling her to do, she is fantastic to work with and she's in very good shape. She can keep going for another two, three years easily at this level of tennis, no problem. She is playing her best right now."
Li's fitness was put to the test on Monday in the Melbourne heat and she admitted to battling fatigue on a day when many matches became survival of the fittest.
"At the end of the first set I was really feeling the heat on the court," Li said. "I couldn't breathe. I was feeling like, what's going on? Lucky I won so easy in the second set."
Li went through the whole post-match news conference without being asked about her husband. A rarity in itself.
Stober said her colourful remarks about Jiang, including threatening him with divorce unless he lost weight and stopped snoring, were only possible because their relationship was so strong.
"Sometimes he reads it or hears about it and he's just shaking his head," Stober said. "He has a laugh about it. Sometimes. Not all the time.
"There have been a few that he hasn't laughed about but they have a fantastic relationship and that's why she can say some of the things she does."
Li said during the Hopman Cup this year that she listened to Jiang for one hour a day, when they were on the tennis court, and he had to listen to her the other 23.
In Sydney last week, when Jiang claimed credit for helping her win a tight semi-final against Petra Kvitova, she brushed off his claims with a: "Yeah, yeah, yeah, yeah."
"She has a smashing sense of humour," Stober added. "How would I describe their situation? It's a love-hate thing sometimes.
"I don't know if I can say this, but she has her moments and she can be a little stubborn. If she doesn't want to listen, well, she doesn't do it. But then she can switch it around and she's on again, it's unbelievable, a great quality to have.
"I think it's good for her that she can get things out of her system and it's okay afterwards. She's cranky at him but it goes away very fast and she's on her way again. I think it's terrific what they have."
Stober said he understood Li's comments about her French Open triumph last year messing with her head during a poor run through the rest of the season.
"It was such a big thing for the country," Stober said. "China has more than a billion people and nobody from there had won a grand slam before. All the other things came into play, media, photos, interviews.
"It's normal for some sort of explosion to happen but she's back on track now. Everything is settled. From the start of our time in Germany, it felt like the start of the next phase of her career."
Li's next opponent will be Australia's Olivia Rogowska, who won 6-3 6-1 over Sweden's Sofia Arvidsson.
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