Six-time Olympic champion Usain Bolt says he is feeling "wonderful" and is ready to run under 20 seconds for the 200m at Thursday's Diamond League meeting in Oslo.
The Jamaican has struggled for early-season form and was beaten in Rome over 100m last week by Justin Gatlin.
Bolt, 26, has been suffering with a hamstring injury but insists he is fit.
He said: "I'm in shape to run under 20 seconds. I'm feeling wonderful. If I execute right, I'll get a fast time."
The fastest time in the world this year is exactly 20 seconds, set by another Jamaican Nickel Ashmeade in Kingston at the start of May.
After his defeat in Rome, Bolt said he was struggling to stay motivated after a historic year in 2012, which saw him retain his Olympic titles in the 100m, 200m and the 4x100m relay.
But he insisted he was not concerned about losing to Gatlin, and was focusing on this year's World Championships in Moscow and regaining the 100m world title he lost in Daegu in 2011.
He said: "It's just one of those things - you win some, you lose some.
"But when it comes to the championships, I always show up. I understand that I will lose every now and again but when the big time comes up I will be ready."
Bolt holds the 200m world record of 19.19 seconds and will be the strong favourite in a field in Norway that contains only three other men who have run under 20 seconds in their careers.
European 200m champion Churandy Martina of the Netherlands could provide the stiffest test, while home favourite Jaysuma Saidy Ndure and American Curtis Mitchell may also challenge.
Great Britain's Perri Shakes-Drayton lines up in the 400m hurdles in Rome against the Olympic silver medallist Lashinda Demus and the Olympic bronze medallist Zuzana Hejnova.
Shakes-Drayton, the European indoor 400m champion, has been in good form this season but only managed a seventh-place finish at the Diamond League meeting in Eugene in a time of 55.74 secs. That race was won by the Russian Hejnova in a world-leading time of 53.70.
Fellow Briton Tiffany Porter will compete in the 100m hurdles, but she will not be joined by Olympic heptathlon champion Jessica Ennis-Hill after she withdrew with an Achilles injury on Monday.
There is British interest in the women's triple jump where 39-year-old Yamile Aldama takes on the Olympic silver and bronze medallists, Caterine Ibarguen of Columbia and Ukrainian Olha Saladukha.
The women's high jump boasts a strong field as two-time former world champion Blanka Vlasic continues her comeback from the injury that saw her miss the London Olympics. She will face current world and Olympic champion Anna Chicherova of Russia and her compatriot the Olympic bronze medallist Svetlana Shkolina.
European indoor 400m silver medallist Nigel Levine finished fourth in Rome last week and will race again in Oslo, as will fellow Briton Martyn Rooney, while Shara Proctor is in action in the long jump.