Garnett was one of two host gym fighters to win North Island titles at the event. Dallas Peneha was more convincing on his way to victory in his 76kg class middleweight fight against Tony Morrell of the Bay City Muay Thai gym in Hastings.
That fight was also scheduled for five rounds but Thompson stopped it in the second. Peneha put Morrell to the floor with kicks in the first and second rounds as he extinguished any hopes Morrell had of gaining revenge for a loss to Peneha earlier this year.
Another host gym fighter, Mike Chettleburgh, scored the fastest victory on the night. A kick to the face of his Rotorua opponent Mike Crossby after just nine seconds ended their 82kg class amateur bout which was scheduled for three rounds.
Crossby appeared to be knocked out for a short period but managed a wave to the crowd as he was taken away by ambulance personnel.
Only two fighters from the host gym recorded losses on the night. Michael McCamish lost his mixed martial arts bout to Whakatane's Joshua Henderson by a first-round submission and popular 13-year-old Kiri Henry lost her 53kg class amateur fight to 24-year-old Whakatane fighter Ursular Marshall-Steele by a unanimous points decision.
"Kiri wanted an opportunity to extend herself and considering the differences in height and age she did well.
"We're all about making our fighters better fighters and better people and Kiri will benefit from this experience," Zero Tolerance trainer Dion Crouch said.
Former boxer Tipene Maniapoto gave another indication of his progress in a new sport with his split-decision win against Mike Kapi of Mana Muay Thai in his 83kg class amateur bout.
The form of Zero Tolerance novice fighters including Keanu Crichton, Bruce Healey and Willie Vincent proved the host gym won't be short of title contenders at future Excessive Force Fights Nights.