In the final, neither fighter managed to secure a throw or score until the closing seconds of the bout when Fletcher got De Villiers in a hold and clung on to the hooter to win 1-0.
Fletcher had been coached at Pinewood by the legendary Don Werner, who died in January. In a message to the coaches and members at Pinewood, a delighted Fletcher said: "Thank you. I love you loads."
The Team England judo player had suffered a nasty injury to her nose in her semi-final clash with Scotland’s Sally Conway who is ranked sixth in the world.
But Fletcher held her nerve to win the fight to add to her victory over Alix Renaud-Roy of Canada in her first contest.
Fletcher's brother Ben had been forced to withdraw from Commonwealth Games through injury.
Meanwhile, in the pool at the Commonwealth Games this evening, Andrew Willis's hopes of getting another medal disappeared after he failed to qualify for the 100m breaststroke final.
Willis, from Bracknell and Wokingham Swimming Club, who won bronze in the 200m breaststroke event last night, finished fourth in his semi-final, outside the automatic qualifying places.
A quick second semi-final meant he failed to qualify as one of the 'fastest losers'.
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