[3] Specialised in Human Resources studies, Shamsul is a former Football Association of Singapore (FAS) referee retired in 2007.
[4] Recognised for his experience as referee instructor and referee assessor at FIFA and AFC level, Shamsul was appointed as part of the instructors' team of the 2012 Summer Olympic Games in London and the 2010 FIFA World Cup in South Africa.
Other highlights of his career include the 1996, 2000 and the 2004 AFC Asian Cup editions, as well as the 2003 and 2001 FIFA World Youth Championships.
The Singaporean also became the only non-African match official at the 2006 African Cup of Nations and guided the United Arab Emirates Football Association (UAEFA) referees as their Technical Director from 2013 to 2015.
Shamsul was then selected to refereed in the quarter-finals between China and Iraq and in the semi-finals between Bahrain and Japan.
Shamsul also officiated the final Group A game between Costa Rica and Poland, becoming the first referee of the competition to perform in three matches.