"I was like, 'How am I going to get through this?" she says in the clip. Her sister, fellow tennis star Venus Williams – whom Serena defeated during the 2017 Australian Open – joked that Serena had an unfair advantage. "It was two against one," she said, laughing. "I want a rematch."
Serena described the thrill of motherhood and her "total opposites" relationship with husband, Reddit cofounder, Alexis Ohanian. "I've always envisioned myself as a mom," she reflects. "But it happened so unexpectedly."
The clip ends with Williams' words of wisdom, as she considers the obstacles she conquered in returning to tennis: "Without fear, without doubt, without discomfort, what is there for a person to overcome?"
The first installment of the five-part Being Serena airs May 2nd on HBO.