While watching his son play rugby for Wellington College on Saturday, Aaron O'Sullivan's worst nightmare as a parent happened.
Fourteen-year-old Puna was hit in the head and stopped breathing during a pile-up.
If it wasn't for the quick thinking of referee Monique Dalley, who is also a police trainee, it's not hard to imagine Puna might not have made it. But not waiting for the ambulance to arrive, Ms Dalley stepped in and started giving CPR.
"We couldn't get a pulse," Ms Dalley recalled. "At this stage he hadn't spoken to us at all, no real responsiveness.
"After 5-10 minutes, he came back and took some big breaths."
Puna was taken to hospital, where he is making a full recovery.
Aaron O'Sullivan appeared on TVNZ1's Seven Sharp tonight alongside Ms Dalley to thank her for saving his son's life.
Watch the full segment in the video above.