Under 80 kilograms fighter Muhammad was controversially selected for the British Olympic team at London 2012 ahead of Cook, then ranked world number one, winning a bronze medal under huge pressure.

Cook left the British team as a result of the dispute, fighting first for the Isle of Man before switching to the Eastern European country following the promise of generous funding. 

He has had few chances to face Muhammad on the circuit in recent years, but beat him last year at the Dutch Open and was confident of more of the same today after a superb semi-final comeback to beat under 74kg champion Masoud Hajizavareh of Iran.

After taking an early lead, however, Muhammad swiftly hit back, frustrating Cook with good defence before picking him off to move 5-1 ahead. 

Cook briefly reduced the arrears by two before attempting a series of speculative spinning kicks in the final moments as his opponent held his resolve to extend his advantage.

After missing May's World Championships in Chelyabinsk with a knee injury, Muhammad's gold medal followed bronze at the Baku 2015 European Games and silver at October's Manchester Grand Prix.

Providing he stays injury free, he is now moving into pole position for the sole British spot at Rio 2016 ahead of world silver medallist Damon Samsun, who lost in his quarter-final today to Albert Gaun of Russian.

Hajizavareh, fighting in the absence of Iranian number one and world champion Mehdi Khodabakhshi, who suffered an injury in losing to Muhammad in Manchester, won the bronze medal match over the Russian.

It was a disappointing day for Iran, however, as Farzan Ashourzadeh lost a battle of reigning world champions in the under 58kg final.

The Iranian was beaten by South Korea's under 54kg champion Kim Tae-Hun, conceding a headkick in the final seconds to fall to a 3-1 loss.

Mexico's Cesar Rodriguez produced one of the loudest cheers of the day from the crowd after taking bronze.

France's Haby Niaré was another of the stars of the opening day, overcoming Turkish rival Nur Tatar in the women's under 67kg division.

Niaré has endured a frustrating time since winning the 2013 world title in Puebla, but had showed signs of returning to her best in beating Tatar to win the Manchester Grand Prix.

She was similarly successful today in a bitterly fought 1-0 victory as Tatar continues to be the nearly-woman of the sport after silver medals at the London 2012 Olympics and 2015 World Championships, as well as bronze at the European Games in Baku.

China Wu Jingyu won the first final of the night over French opponent Yasmina Ariez in the under 49kg competition.

The Beijing 2008 and London 2012 Olympic champion is considered one of the strongest fighters across all the women's divisions, and she showed why, never letting her opponent close enough to truly challenge. 

It was not won without controversy, however, as a scoreboard malfunction briefly showed Ariez 7-6 ahead with seconds left before the system was re-adjusted after a lengthy delay.

Thailand's under 46kg world champion Panipak Wongpattanakit of Thailand stepped up in weight to win bronze.

Technical glitches aside, it was a successful opening day here, with impressive crowd support for an evening session also attended by WTF President Chungwon Choue, as well as guests including Kiumars Hashimi and Michael Fennell, respective Presidents of the National Olympic Committee of the Islamic Republic of Iran and the Jamaica Olympic Association.

Four more finals are due to take place tomorrow, before the WTF World Cup brings the season to a conclusion on Tuesday and Wednesday (December 8 to 9).

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