Beijing: Rivals Usain Bolt and Justin Gatlin are expected to set up a 200m showdown and Olympic champion Kirani James will go for gold in the men`s 400m at the world championships on Wednesday.
Bolt and Gatlin cruised into the 200m semi-finals and the tall Jamaican is oozing confidence after Sunday`s tight 100m win over the controversial Gatlin, who has served two doping bans.
"I`m always confident, man," the six-times Olympic champion and world record-holder said, when asked whether he expected to beat Gatlin again in Thursday`s final in Beijing.
"I knew the 200 was going to be harder because I`m not in the best of fitness," added Bolt, who struggled with pelvic joint pain earlier in the season.
"Everybody knows the 200 actually means more for me than the 100 so I`m trying to get through the rounds as comfortably as possible and using as little energy as possible," he said.
James will look to add world gold to his Olympic 400m title but in what is shaping as a thriller, he will be pushed hard by contenders including defending champion LaShawn Merritt.
Britain`s Mo Farah, who won the 10,000m on Saturday, will begin his bid for a distance double when he runs the 5,000m heats in the morning session at the Bird`s Nest stadium.
The women`s 200m heats are missing 100m winner Shelly-Ann Fraser-Pryce and America`s Allyson Felix, who both opted out, blowing the field wide open.
Much-decorated Jamaican Veronica Campbell-Brown could enjoy a golden swansong, although countrywoman Elaine Thompson, Nigeria`s Commonwealth Games champion Blessing Okagbare and Dutch 100m silver medallist Dafne Schippers could also shine.
Other finals on Wednesday include the women`s pole vault, 400m hurdles and 3,000m steeplechase, as well as the men`s javelin.