Berlin: The athletics world championships get underway on Saturday when all eyes will be on the heats of the men`s 100 meters ahead of Sunday`s final.
Usain Bolt and Tyson Gay are the big draw in the morning heats and afternoon quarter-finals with their expected final showdown scheduled for 1935 GMT Sunday night.
The first medals of the championships are up for grabs in the men`s 20km walk (1100 GMT) with Russia`s Olympic champion Valeriy Borchin favourite.
There are two more finals in the evening session - the women`s 10,000 meters and men`s shot.
The 10,000 has suddenly become much more open after Friday`s injury withdrawal of 2005 and 2007 champion Tirunesh Dibaba, though Ethiopia should still push strongly to make it six golds in a row in the race.
The United States have been similarly dominant in the shot and again have four strong contenders, including defending champion Reese Hoffa and 2005 winner Adam Nelson. Poland`s Olympic champion Tomasz Majewski could upset them though and seems to have hit top form at just the right time.