[2] Having built up an undefeated record on the British Muay Thai scene, Watson made his first foray into Oriental kickboxing rules[broken anchor] and his K-1 debut at the K-1 UK MAX Tournament 2007 Pain & Glory in London, England, on 20 May 2007.
After outpointing Killy Guelladrss in the quarter-finals and knocking out Harvey Harra in the semis, he suffered the first loss of his professional career at the hands of Sophiane Allouche in the tournament final.
[3][4] In November 2008, he won the UK qualifying tournament for the second season of The Contender Asia in Watford, England, taking decision wins over Tim Thomas and Craig Jose before stopping Chris Shaw in the final.
[5] After wins over international opponents such as Halim Haryouli[6] and Kouider Oukbi[7] in 2009, Watson took a big step up in class to fight Buakaw Por.
[14][15][16] Towards the end of the year, Watson joined the cast of The Challenger Muay Thai reality television show, the unofficial successor to The Contender Asia, in Kuala Lumpur, Malaysia.
He defeated Cyrus Washington,[19] Cédric Muller in a rematch,[20] and Mostafa Abdollahi over sixteen weeks on the road to the final where he faced Tum Mardsua in December 2011.
[23][24] When Andy Souwer withdrew from his fight with Johann Fauveau at Urban Boxing United in Marseille, France, on 19 May 2012, Watson replaced the Dutchman in the ISKA World Super Welterweight (-69.5 kg/153.2 lb) Oriental Championship match.
[27] He was set to fight Aikpracha Meenayothin in the WMC Prince's Cup 2012 in Bangkok in July 2012 but was replaced by Marco Piqué for undisclosed reasons.
Aikpracha cut him after landing elbows and a big knee in the second, and pressed home his advantage in the third, managing to trip and dump the Englishman several times.
[35][36] In yet another close but unsuccessful fight with a top Thai, Watson fought to a draw with Kem Sitsongpeenong in a three-round bout at Yokkao Extreme 2013 on 26 January 2013 in Milan, Italy.
[40][41] He was initially scheduled to rematch with Aikpracha Meenayothin at MAX Muay Thai 3 in Zhengzhou, China on 10 August 2013[42] but his opponent was instead changed to Sitthichai Sitsongpeenong, and Watson lost by way of a controversial decision.
[43][44] He had a scheduled match with Albert Kraus at Glory 10: Los Angeles - World Middleweight Championship Tournament in Ontario, California, United States on 28 September 2013[45] but was unable to compete due to visa issues and was replaced by Ky Hollenbeck.