RIO DE JANEIRO - Neymar's Brazil face Honduras at the Maracana, Usain Bolt runs in the 200m semi-finals, and lone Russian athlete Darya Klishina is in the long jump on Wednesday in Rio.
Brazil's Neymar in action against Iraq during the 2016 Olympic Games first round match in Brasilia, on August 7, 2016
Elsewhere on day 12 of the 2016 Olympics Copacabana hosts the women's beach volleyball final which starts at midnight (0300 GMT) and China are set to complete their mopping up operation at the table tennis.
Barcelona superstar Neymar and his teammates are desperate not to suffer the same fate as Marta and the Olympic hosts' women's team, dumped out by Sweden at the same stage on Tuesday.
With his first goal of the competition in the quarter-final defeat of Colombia, Neymar helped lead Brazil into the last four at the Olympics.
Waiting for them in this David and Goliath contest are Honduras after the Central Americans stunned South Korea.
Germany's men are trying to keep tabs on their women's team and make it to the final but first they must overcome Nigeria.
Bolt is at the Olympic Stadium for the latest step towards his 'triple triple' sprint gold with his race due off at 10.08pm (0108 GMT Thursday).
With the first leg - Sunday's electric 100m win - secure Bolt needs Thursday's 200m final and the 4x100 relay to achieve what he refers to as 'immortality'.
Four of Wednesday's 16 gold medals concern track and field; men's 3000m steeplechase, and women's 200m and 100m hurdles and long jump.
Klishina comfortably qualified for the long jump.
She is flying the flag for Russia at the Olympic Stadium in the wake of the doping scandal that has rocked track and field.
Table tennis concludes at the Riocentro venue with the men's team final. China are strong favourites to pull off their third consecutive Games' clean sweep of medals.
Badminton's first gold is mixed doubles with Indonesia's Tontowi Ahmad and Liliyana Natsir facing Chan Peng Soon and Goh Liu Yong of Malaysia.
At the boxing, Uzbekistan's Shakhram Giyasov takes on Daniyar Yeleleussinov of Kazakhstan for the welterweight title.
Taekwondo enters the gold medal fray for the first time at Rio 2016 with the men's 58kg and women's 49kg.
The 3,000-year-old martial art is embracing more 21st century technology to bolster "transparency". Fighters will have electronic sensors in their helmets to detect kicks to the head.
Women's wrestlers contest titles in 48kg, 58kg and 69kg, whilst at Marina da Gloria there are the men and women's 470 regattas.