Trailing by 17cm in third, the Otago athlete pulled out a personal best of 5.62m to win the women’s long jump (T47) by 3cm.
"I knew I had to give it everything; the leaders weren’t ridiculously far ahead," Grimaldi (19) told the Otago Daily Times yesterday afternoon.
"It’s crazy still, I can’t believe it."
She knew she had won the bronze medal before her final jump, and leapt into the air in an emotional celebration when the winning distance was announced.
Grimaldi headed into the event with a personal best of 5.41m.
"I was super happy with the final jump."
Her win was New Zealand’s first Paralympic athletics medal since 2004.
"The support’s been amazing.
"I just got back into a Wi-Fi zone and my phone has just blown up with messages and notifications from people back home.
"My family’s here. I didn’t get to see them before I competed so it was awesome walking out and seeing them in the crowd with the New Zealand flag."
She was enjoying her time in Rio and exploring the Olympic village.
While the long jump was her main event, Grimaldi, who was born without a right hand, will also compete in heats for the 100m tomorrow and 200m on Friday.
"I’m looking forward to them. The 100’s not my strongest event, but I’ve been working on a lot of speed lately so it will be good to see how that goes."
Her coach, Brent Ward, was thrilled she was able to pull it together when it counted.
"She really attacked the board that last jump," he said, from Dunedin, where he watched the event.
"It looked good right from a few strides out."
Grimaldi won bronze at last year’s IPC Athletics World Championships.
Cuba’s Yunidis Castillo won silver with 5.59m, and Australian Carlee Beattie bronze with 5.57m.