(CNN) -- Former world No. 1 Caroline Wozniacki has fired Spanish coach Ricardo Sanchez after just two months and decided to return to working with her father Piotr.
The Dane slipped to fourth in the WTA rankings after a quarterfinal exit at the recent Australian Open, where she once again failed to secure a first grand slam title.
Troels Christensen, a journalist with the Danish newspaper Ekstra Bladet, told CNN how Sanchez had struggled to penetrate the close bond Wozniacki enjoys with her Poland-born father.
"Caroline and Piotr are mentally very tight," Christensen said. "It's very hard to break into the circle. He is not the first one has experienced that.
"It was more Piotr's idea than Caroline's and I don't think she ever got used to him. They had agreed that they should sit down after the Australian Open and discuss the situation."
Christensen said the tactical advice Sanchez gave Wozniacki during last month's Melbourne grand slam appeared to be ignored by the 21-year-old.
"He must have seen that his input did not come out on the court. When the Danish press confronted Caroline with his analysis, she would not comment," Christensen said.
"I sensed when I got to Melbourne that something was wrong because the Wozniacki team are usually in good spirits, but they were not this time."
Despite the split with Sanchez, Christensen stressed that there was still a high level of respect between the three.
"They like him very much and they're good friends. In my opinion they should have been more clear about who should do what and who is entitled to do what before they started working together."
Wozniacki's failure to capture a grand slam title during her spell at the top of the world rankings meant she faced constant questioning on the subject.
Christensen said Wozniacki is also now facing criticism from a vocal minority of Danish tennis fans who find it hard to identify with her lifestyle.
"There is a part of the Danish population who are irritated by her and think that she is not very Danish, she's very Polish in her ways because of her father," he said.
"They say, 'She is living in Monaco, not paying her taxes blah blah blah...' But I think it's a minority, but they are very loud. If you see the forums and newspapers' websites, people are a little bit skeptical about her chances of winning a grand slam."
Wozniacki will look to return to winning ways at this month's WTA tournament in Qatar, where last year she lost in the final.
This year's entry list includes new No. 1 and Australian Open champion Victoria Azarenka.