World No 1 Simona Halep will be without a coach for the first few months of the 2019 season after her Australian coach Darren Cahill quit due to "family reasons".
Halep, who has a bye into this week's Sydney International second round, has worked with the former Australia Davis Cup captain since 2016.
But the Romanian, who won her maiden Grand Slam at the French Open last year, said she would not replace him until at least the clay-court season.
"The situation is that for the next three to four months, I don't want to take the coach; I go with the flow and I see how it works," Halep told the WTA website.
"He took the decision because of family and family always comes first. I wasn't disappointed or upset, I fully understood. We have a very good relationship."
Halep was diagnosed with a herniated disc in October which ruled her out of the season-ending WTA Finals, but still retained her top ranking for a second straight year.
The 27-year-old believes she is now pain-free and feels this week will be the real test of her fitness as she prepares to face the winner of the match between Jelena Ostapenko or local hope Ashleigh Barty.
"The back was good for the off-season. I didn't have pain and I trained 100 per cent, I played some sets, some matches," Halep said.
"No pain, no stress, but you never know until the official matches, so I'm waiting for this week to see how I feel. I have no pressure, but I'm motivated to see how good I can be this year.
"Six weeks I did nothing, just in the gym to do exercises every day for one hour. No tennis. It was a long time; it's going to be a tough start because I have almost three months without official matches."
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