Double Olympic champion Jade Jones and twice European title holder Lauren Williams won gold during the three-day tournament in the under-57 kilograms and under 67kg classes respectively.

There were silver medals for double world champion Bianca Walkden, in the over-67kg class, and double World Championship medallist Damon Sansum, in the under-80kg category.

Bradly Sinden, also a world medallist last year, finished with bronze in the under-68kg class..

In addition, teenager Rebecca McGowan defeated former Olympic title winner and world champion Milica Mandic in her first bout while Liverpool's Josh Calland beat Belgium's 2015 world champion, Jaouad Achab.

There were also Grand Prix debuts for Molly Dunbavin and Kyla Julien.

"I am extremely pleased for a couple of reasons," said Hall.

"We bid for Grand Prix events for exactly what was created over the weekend.

"That was home advantage and an ability to raise the profile of the sport plus an opportunity for the best taekwondo athletes on the planet to come to Manchester and for our fighters to compete against them to see what level they are at.

"Considering there were only eight weight groups contended, we got five medals in eight of those groups.

"So, I am extremely pleased with the number of ranking points we pulled off on the journey to Tokyo 2020."

The final medal tally matched last year's total from the London Grand Prix.

In contrast, last month British fighters took three medals at the Taoyuan Grand Prix in Chinese Taipei, none of which were gold.

"We can't be at our very best for every single event," said Hall.

"But this was one we had on the calendar we wanted to hit. 

"And the athletes did just that.

"You are a fool in sport if you think it is always going to meet your expectation but, on this occasion, it came right.

"This is a testament to our world class performance programme in Manchester.

"It provides the best athletes with the best service they need to continue to win at the very highest level.

"We also have a sustained track record of developing athletes in the proper way.

"Part of that is blooding them in fields like we had at the Grand Prix."

Next May, Manchester will host the first Taekwondo World Championship to be staged in the United Kingdom.

"Manchester is the home of GB Taekwondo and crowds are getting larger," added Hall.

"They are also getting more informed.

"There is an appetite to watch and support the team at big events.

"So, it will be brilliant to have the World Championships at the Manchester Arena.

"I think there will be an incredible atmosphere and I am sure there will be some memorable golden moments."