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Dayron Robles was the clear favorite, having set the world record just two months earlier. He didn't disappoint leading the semi-final round by almost a tenth of a second, a huge margin on this level. In the final, Robles was out first, clearly ahead by the first hurdle; he pulled away to a clear victory. The two Americans, David Payne and David Oliver were clearly separating from the others for second place, Payne slightly ahead of Oliver, with only Ladji Doucouré within a stride of Oliver. Doucouré looked to be faster, and on the final dash to the finish line was clearly gaining on Oliver, who himself was gaining on Payne to make the finish much closer. Robles more than doubled his margin from the semifinal round, almost a quarter of a second ahead of Payne.
Background
This was the 26th appearance of the event, which is one of 12 athletics events to have been held at every Summer Olympics. Four finalists from 2004 returned: gold medalist Liu Xiang of China, silver medalist Terrence Trammell of the United States, fourth-place finisher Maurice Wignall of Jamaica, and eighth-place finisher Ladji Doucouré of France; fifth-place finisher Staņislavs Olijars of Latvia was entered but did not start. Since winning the gold in 2004, Liu had broken the world record in 2006 and won the world championship in 2007. However, Dayron Robles of Cuba had bettered Liu's mark two months before the Games and was favored over the home country hero. Further, there were rumors of Liu being injured.
Belarus and the Cayman Islands each made their first appearance in the event. The United States made its 25th appearance, most of any nation (having missed only the boycotted 1980 Games).
Qualification
Each National Olympic Committee (NOC) was able to enter up to three entrants providing they had met the A qualifying standard (13.55) in the qualifying period (1 January 2007 to 23 July 2008). NOCs were also permitted to enter one athlete providing he had met the B standard (13.72) in the same qualifying period. The maximum number of athletes per nation had been set at 3 since the 1930 Olympic Congress.
Competition format
The competition used the four-round format previously used in 1960 and since 1988, still using the eight-man semifinals and finals used since 1964. The "fastest loser" system, also introduced in 1964, was used in the first round.
The first round consisted of six heats, with 7 or 8 hurdlers each. The top four hurdlers in each heat, along with the eight next fastest overall, advanced to the quarterfinals. The 32 quarterfinalists were divided into four heats of 8 hurdlers each, with the top three in each heat, and the four next fastest overall, advancing. The 16 semifinalists were divided into two semifinals of 8 hurdlers each; the top four hurdlers in each advanced to the 8-man final.
Records
Prior to this competition, the existing world record, Olympic record, and world leading time were as follows:
Dayron Robles of Cuba winning the 110 meters hurdles
Dayron Robles (CUB)
Liu Xiang (CHN)
Barbados
Cayman Islands
Greece
South Korea
Cuba
Great Britain
Jamaica
Russia
Uzbekistan
Croatia
United States
Spain
Bahamas
Netherlands
Trinidad and Tobago
Slovenia
Colombia
Czech Republic
Puerto Rico
Haiti
Pakistan
France
Nigeria
Belarus
Japan
Poland
Hungary
Brazil
Madagascar
Latvia
Qatar
Georgia
