Tan Boon Heong (, born 18 September 1987) is a former World No.1 Malaysian professional badminton player in the men's doubles event. Career 2004-2006 Tan was previously paired with Hoon Thien How, with whom he won the World Junior Championships in 2004 and a silver medal at the 2006 Asian Badminton Championships. 2006 Nearing the Doha Asian Games in 2006, Rexy Mainaky (the Malaysian doubles coach) decided to split them up and partner Tan Boon Heong with Koo Kien Keat instead. This move, nevertheless, proved to be spot-on as this pair went on to become the Asian Games champion, winning the gold medal in their maiden outing by defeating the then Chinese world champions, Cai Yun and Fu Haifeng, in the quarterfinals, Indonesia's Markis Kido and Hendra Setiawan in the semifinals, and finally Luluk Hadiyanto and Alvent Yulianto, also from Indonesia, in the finals. They are the youngest men's doubles to win gold medal at Asian Games at the age of 21 and 19 respectively. 2007 2007 was the best year for Koo and Tan. They became the first qualifiers to win the Superseries at the Malaysian Open. They also became the World No.1 that year. They won their first All England Open after beating Chinese pair, Cai Yun and Fu Haifeng in straight games. 2008 They competed at the 2008 Olympics, reaching the quarter-finals. 2009 At the Japan Open, Tan set the world record for badminton smashes at 421 km/h. This was done under lab conditions and recorded by Yonex representatives, and not in an official match. Later, he and Koo Kien Keat won the bronze medal at the 2009 World Championships. 2010 At the 2010 BWF World Championships, Tan and partner Koo Kien Keat launched themselves into the semifinals after beating Korean rivals Lee Yong-dae and Jung Jae-sung. In the semifinals they defeated China's Guo Zhendong and Xu Chen 21–14, 21–18. Tan Boon Heong and Koo Kien Keat were the first Malaysian pair to enter a World Championships final in 13 years. In the finals, they played China's Cai Yun and Fu Haifeng and lost 21–18, 18–21, 14–21. The year 2010 was the last time Koo and Tan ranked World No. 1. 2011 At the 2011 All England Open, Tan and Koo defeated 2008 Olympic champions Markis Kido and Hendra Setiawan in the quarterfinals. They then defeated World champions Cai Yun and Fu Haifeng 21–11, 23–21. They lost