The 19-year-old went into the competition for athletes with limb deficiencies ranked second in the world and was third at last year's world championships.
The last medal won by a New Zealand woman in a Paralympic field events was the bronze Leslie Mancktelow collected in the long jump B3 in 1988. The last medal won by New Zealand in para-athletics at a Paralympic Games were the two golds and a bronze won by Peter Martin in Athens in 2004.
Liam Malone looks in good form to add another medal on the track after producing the second fastest time in the men's 100m T44 heats, winning his heat to advance through to the semifinals in a time of 10.90 seconds.
Grimaldi had a sense of performing well in Rio.
"I have had a couple of good practice competitions leading into it so knew there was a possibility of jumping that far," said the Dunedin athlete, who will also compete in the women's 100m 200m T47. "I knew I had it in me. It was pretty awesome it came out finally on that lust jump."
Dubber gave New Zealand's campaign in the pool a strong start with bronze in the final event of the day. Dubber surged late to finish third behind Chinese duo Ke Liting and Zhang Ying in the women's 100m backstroke S7. Fellow Kiwi Nikita Howarth was fifth.
Also in the pool, Cameron Leslie was eighth in the men's 200m freestyle S5 final.
Kiwi cyclist Kate Horan was edged out of the medals after finishing second in the bronze-medal ride in the 3km pursuit C4 event. Horan led Megan Fisher at the 2km mark but the American fought back to finish in a time of 4:04.081. Horan was less than a second back in 4:04.437.
All six New Zealand Paralympians competing in Rio yesterday broke their previous personal bests.