In case you were wondering, Serena Williams may not be throwing in the towel on her career just yet. At least not according to her coach.

In an interview with People, her coach, Patrick Moratoglou, says the tennis star still has more to do, more to accomplish.

“I don’t think she planned [retirement] for this certain moment. She’s dedicated all her life to tennis since she was a kid,” says Patrick Mouratoglou. “So the day she will retire, she will feel like she’s giving an end to 40 years of a life.”

“I don’t think she will stop until she at least wins a Grand Slam, because she came back to win Grand Slams. She doesn’t quit.”

The 23-time Grand Slam winner received a standing ovation as she was leaving the court at the end of last week’s game. Waving back to the crowd and touching her heart in gratitude led to suspicion that she had played her final game. The press conference that followed led to even more speculation when Williams left early. Her eyes were filled with tears.

Mortatoglou says the media speculation comes too soon.

“I have to believe it and she has to believe it, too. If she [doesn’t], she would stop. After all she’s achieved in her career, at her age, having a baby for the first time, having a family — it was an incredible effort to come back to tennis,” says the coach. “Unbelievable effort. Mental effort, physical effort, so many hours to get back in shape. She would never even start that if she didn’t think she was able to win a Grand Slam.”

He says, “That’s how Serena is really exceptional. She puts the standards so high for herself, and she finds a way to match those standards, whatever she does.”