Serena Williams' coach Patrick Mouratoglou says she must "face reality" and adopt "a different strategy" in order to win another grand slam title.
Williams, 38, remains one short of Margaret Court's all-time record of 24 grand slam singles titles and has failed to win one since giving birth to daughter Alexis Olympia in September 2017.
Since becoming a mother the American, knocked out of the Australian Open in the third round last month, has lost in four major finals.
"We have to accept the fact that it is not working," Mouratoglou, who has coached Williams to 10 grand slam singles wins, told BBC Sport.
"Maybe come back with a different angle, a different strategy and different goals so she can make it.
"She does feel positive, she feels negative too because it is a failure when she doesn't win a grand slam.
"We have to face reality, but she is positive that she can make it otherwise she probably wouldn't be on a tennis court anymore.
"She believes she can make it and I believe it too. She's not that far, but we have to change a few things."
Williams, beaten by China's 27th seed Wang Qiang in Melbourne, returned to tennis four months after giving birth.
She won her first tournament in three years at the Auckland Classic prior to the Australian Open to make it 73 career singles wins in total.
"It's difficult to know how many chances she will have," Mouratoglou added. "I don't know how long she is going to be able to play.
"But being able to reach four grand slam finals says a lot about her level, and she's not that far."
