the K-1 World Grand Prix 2007 in Hong Kong on August 5, 2007 before going up against Ray Sefo at the K-1 World Grand Prix 2007 in Seoul Final 16 on September 29, 2007. He won the fight at the end of the first round by TKO (corner stoppage) when Sefo did not answer the bell. As a result of his victory, Aerts qualified for his 15th consecutive K-1 World Grand Prix . The K-1 World Grand Prix 2007 Final was held on December 8, 2007, at the Yokohama Arena. After a quick knockout of Junichi Sawayashiki in the quarter-finals, he met two-time K-1 World Grand Prix winner Remy Bonjasky in the semis and dominated him en route to a unanimous decision (30-29, 30–27, 30–28) win which would take him into the final for a rubber match with defending champion Sem Schilt. Midway through the first round, Aerts went down in pain clutching his right knee. He was unable to continue due to injury once again and Schilt regained the title. 2008–2011: Later K-1 career and legend status Aerts began 2008 with a TKO win over South African giant Jan Nortje at the K-1 World Grand Prix 2008 in Fukuoka on 29 June, before meeting Semmy Schilt for the fourth time at the K-1 World Grand Prix 2008 in Seoul Final 16 on September 27. Aerts won by majority decision (30-29, 30–29, 30-30) to bring their rivalry to 2-2 and qualify for the K-1 World Grand Prix 2008 Final which was held on 6 December 2008. He was eliminated at the first stage by K-1 Heavyweight Champion Badr Hari. Aerts gave a poor performance in the match, and was knocked down less than twenty seconds into round one. In the second round, Hari dominated even more and forced the referee to stop the fight. Following this poor showing, many critics and fans believed that, at 38 years old, Aerts was too old and past his prime. Nonetheless, he was determined to return to form and began training under Thom Harinck again in early 2009. With Harinck back in his corner, Aerts faced Errol Zimmerman in a superfight at the K-1 World Grand Prix 2009 in Yokohama. Although the fight went to an extra round decision which Aerts won unanimously (10-9, 10–9, 10–9), he looked like a much improved fighter. Following this, he knocked out former world cruiserweight boxing champion Yosuke