Jessica Ennis may be the face of the London 2012 Olympics, but Usain Bolt is the face of the sport worldwide, and both superstars will be in action on day two (Saturday) at the Olympic Stadium.
At the last competition Bolt took part in, he was beaten – not just once, but twice. World 100m champion Yohan Blake pipped Bolt to both the 100m and 200m titles at the Jamaican Championships, and the pair will renew their rivalry tomorrow in the first round of the 100m – although they will, of course, be in separate heats.
Team-mate Asafa Powell will be hoping his injury problems do not get in the way, while USA field a strong trio in the form of Tyson Gay, Justin Gatlin and Daniel Bailey.
Ennis, meanwhile, currently holds the overnight lead in the Heptathlon after a stunning first day in which she flew to a 12.54 national record in the 100m Hurdles and backed it up with a 22.83 PB in the 200m.
But tomorrow she will need to be on her guard as World champion Tatyana Chernova excels in all three events on day two – the Long Jump, Javelin and 800m. Austra Skujyte could still make inroads into Ennis's lead to maintain her medal position.
Borchin's dominance under threat?
Aside from the conclusion of the Heptathlon, there will be a handful of other finals contested tomorrow evening – the first of which is the men's 20km Race Walk and takes place late in the afternoon on the streets of London.
Valeriy Borchin is the reigning Olympic champion and has also won the two World Championships since Beijing. But he was less than convincing at the World Race Walking Cup earlier this year and if the Russian is unable to turn his form around, then World Cup winner Wang Zhen could take advantage and win China's first Olympic gold in a men's race walking event.
All of the big medal favourites in the women's discus made it through to tomorrow's final. In qualifying, very little separated the likes of World leader Darya Pishchalnikova, European champion Sandra Perkovic, defending champion Stephanie Brown-Trafton, and the top two from last year's World Championships, Li Yanfeng and Nadine Muller.
The men's Long Jump may not prove to be the highest-quality in Olympic history, but it should at least be extremely competitive. Greg Rutherford and Chris Tomlinson carry the host nation hopes, but USA's Marquise Goodwin, Australia's Mitchell Watt and European champion Sebastian Bayer will all be tough to beat.
All eyes on Farah in the 10,000m
Half an hour after the Heptathlon draws to a close, the expectant home crowds will turn their attention to Mo Farah who opens his Olympic campaign with the 10,000m final. The World 5000m champion is gunning for two gold medals in London, but he has said that the longer race will be his primary focus.
Ibrahim Jeylan, the Ethiopian who beat Farah to the World title last year, will not be in London, but that does not mean Farah will have it easy as he is up against one of the greatest distance runners of all time, Kenenisa Bekele. He is joined by his brother, Tariku, while World leader Wilson Kiprop is one of three strong Kenyans.
At the other end of the distance spectrum, the women's 100m reaches its climax with Shelly-Ann Fraser-Pryce out to defend her title. In today's heats, Carmelita Jeter and Blessing Okagbare also looked in form to challenge for a medal, but before they get to the final they will have to safely make it through the semi-finals, which will be held two and a half hours prior.
Places in final up for grabs in one-lap events
The heats of both the women's 400m and the men's 400m Hurdles saw all the main contenders progress. But tomorrow's semi-finals will be more telling as athletes will not only have to guarantee their place in the final, but they will also want a good lane draw.
The first of the women's 400m semis boasts four women with sub-50 personal bests – including 2009 World champion Sanya Richards-Ross and reigning Olympic champion Christine Ohuruogu. The other two semi-finals are slightly less loaded with Amantle Montsho going in the second and World leader Antonina Krivoshapka in the third.
The men's 400m Hurdles semi-finals sees World leader Javier Culson take on defending Olympic champion Angelo Taylor, while World champion Dai Greene faces Felix Sanchez. The third semi-final appears to be the easiest and US Champion Michael Tinsley will be expected to make his first major championships final.
Isinbayeva begins title defence
The women's Pole Vault is one of the events that will get underway tomorrow, and reigning Olympic champion Yelena Isinbayeva will be out to prove that her recent no-height was nothing more than a little blip. Expect her to enter the competition in the later stages though, perhaps at the automatic qualification height of 4.60m.
The other heats that begin tomorrow are for the men's 400m and the women's 3000m Steeplechase.