As a player, Tan played for Kedah in three Malaysia Cup finals from 1988 to 1990. He lost the 1988 and 1989 finals, but finally won the trophy in 1990. Tan made an appearance for Malaysia in a match against Aston Villa on 20 May 1991. In September 1991, he was part of Malaysia B team managed by M. Karathu for TAAN Cup, an invitational tournament in Kathmandu Nepal. Malaysia B team won the tournament beating Tiong Bahru of Singapore 2–0.
Managerial career
Tan was the assistant coach to K. Rajagopal from 2004 to 2013. Under Rajagopal and Tan, Malaysia achieved many good results such as reaching the quarter-finals of 2004 AFC Youth Championship and qualifying for the 2006 AFC Youth Championship. Malaysia also ended their trophy drought in regional football by winning the 2009 SEA Games and 2010 AFF Championship. Tan appointed as Kedah head coach in 2014 after Dave Mitchell was instructed by the Kedah FA exco to take a "rest" following unsatisfactory results in the first half of the Malaysia Premier League. In 2015, he helped Kedah win the Premier League to gain promotion to the Super League. He was named the M-League's Best Coach of the Year at the 2016 National Football Awards following the success in Malaysia Cup, finishing third in the Super League and reached the FA Cup semi-finals. In 2017, he made a return as the assistant coach of Malaysia under Nelo Vingada. He take over as Malaysia head coach after Vingada stepped down following a string of poor results. In the preparation for the 2018 AFF Championship, Tan had mentioned through an article published by the FOX Sports Asia that Malaysia are underdogs team and hope their country fans will not put their hope too much despite being drawn into a favourable Group A consisting of Vietnam, Myanmar, Cambodia and Laos, adding the favourites in the group would be Vietnam and hope their players will not feel too much pressure as there had been a lot of expectations from the fans. Surprisingly, he managed to lead Malaysia into the final after eliminating the tournament defending title as well five times champions of Thailand in the semi-finals. This was continued in the finals first leg when the Malaysian team under his led also managed to hold the tournament favourites of Vietnam 2–2 at home in their second meet in the tournament despite the latter had already scoring two goals in the first half. However, in the second leg in Hanoi, his team failed to repeat the same success when the favourites scored a goal in the early first half of 6th minute and began tightening their defence, resulting in a 2–3 aggregate until the end of the match as a result of which Malaysia became the runners-up for the third time. Tan continued to lead the Malaysian team in the 2022 FIFA World Cup qualification after he been reward by the Football Association of Malaysia to manage the team for another two years until his contract ended in 2020. Although the team under his management able to easily routed Timor-Leste in the first round by 12–2 in aggregate to proceed into the second round, the team only able to defeating Indonesia by 3–2 in an away match before losing two matches against United Arab Emirates in home by 1–2 and against Vietnam by 0–1 in an away match where they meet again for the fourth time through his managerial career despite of all the promises Tan has made earlier to the Malaysian fans before the competition started. After the two consecutive defeats, he then led Malaysia to win one of the most famous matches in their history, beating neighbour and Southeast Asian powerhouse Thailand 2–1 to extend its unbeaten streak at home to Thailand, and Indonesia 2–0 also at home to keep maintaining Malaysia's World Cup dream alive.
