While relaxing at Gunyah Beach in Bundeena, Australia, Blake Donaldson heard screams from the ocean. Mangyon ‘Mani’ Zhang, 57, was being attacked by a shark. Without hesitation, Donaldson dove into the water to help her.

“I just [had] to jump in,” Donaldson told 60 Minutes Australia. “I wasn’t thinking about the shark… Either you watch someone drown or you go out and help them.”

Donaldson managed to lift Zhang onto a paddle board and bring her to shore. His partner, Ellen Melchert, applied first aid to a 15-inch wound on Zhang’s leg until emergency crews arrived.

Zhang recalled the horror: “I can’t move. I can’t even think. I can’t breathe.” Paramedic Marco Aielli confirmed she’d lost a “catastrophic amount” of blood and was “very unwell.”

Zhang later underwent surgery and has since reunited with Donaldson. Overwhelmed with emotion, she told him, “You saved my life. Words … cannot express … how thankful I am.”

Though he humbly shrugged off the praise, Donaldson’s bravery made all the difference that day.