The land of the rising sun now has six from this campaign and could even afford a slip up by its most likely champion.
Kosei Inoue faltered badly in the men's under 100kg category where he had never before lost in an international championship.
But this day was all about Anno who was bundled out in the first round of the Games in 1996 and 2000 despite landing four world titles between 1997 and 2003.
Unsurprisingly the first round was the one that made her most nervous as she stepped onto the mat in Athens.
"I am so glad because in Sydney I lost in the first round. After the first round here, I felt emotionally very calm," she said.
"In Sydney I lost weight because I was so nervous but this Olympics I kept my weight steady and mentally I was much stronger."
That allowed her to edge a 9.41 minute marathon in her semi-final against France's Celine Lebrun and then snatch gold from China's Xian Liu 22 seconds from the end of the final.
WEIGHT AN ISSUE
Liu was something of an unknown quantity in this division having stepped down from the over 78kg category in order to take China's place at the Games.
She lost 15 kilos to make the weight but did not lose any power in so doing.
"The coach believed I would perform best in this category so it was decided during our training stage that my weight should be reduced by 15kg," she said.
That huge loss did not effect her but she could not match the skill of Anno, who was also keen to talk about her weight.
"I gave it everything I had as I knew I had just one chance. I paid very close attention to watching my weight to ensure I had full strength."
Inoue's shock defeat opened up the men's draw and allowed an unlikely contender to come through and take gold.
Ihar Makarau of Belarus beat Jang Sung-ho of Korea in the final with a leg-grab pick-up technique that scored waza-ari.
Jang hit back, scoring yuko with osoto-gari, but that score was lower than Makarau's and he had to settle for silver.
Makarau was feeling modest when he spoke in the press conference afterwards, attributing his victory to the lap of the Gods.
"I was hoping for the gold medal today but I was just more lucky than the others - it certainly was my lucky day."
Makarau had a fairly kind draw as he made his way to the final but earned the honour of the man who beat the man when he knocked out Elco van der Geest of the Netherlands in the semi-final.
It was he who had dethroned Inoue.
Despite winning world silver in 1999 and bronze two years later, Jang still felt his medal was unexpected.
"I never expected a medal before I came here but I felt mentally strong enough."
The bronze medals were won by Germany's Michael Jurack and Ariel Zeevi of Israel who enjoyed the most vocal support all day from a huge Israeli following.
They beat the two men who defeated Inoue, leaving van der Geest, beaten by Zeevi, and Azerbaijan's Movlud Miraliev, without a medal.
The women's bronze medallist were Lucia Morico of Italy, who defeated Anastaysia Matrosova of Ukraine, and Cuba's Yurisel Laborde who denied Lebrun a medal after her earlier marathon efforts.
