Williamson (left) is the only sprinter guaranteed a place in the 100m
UK Athletics have named one 100m runner for Beijing as they wait for Thursday's High Court ruling on Dwain Chambers' appeal against his Olympic ban.
Simeon Williamson is guaranteed his place in the team after finishing second behind Chambers at the UK trials at the weekend.
However, the remaining two places will not be confirmed until the outcome of Thursday's ruling is known.
The British Olympic Association has until 20 July to name its final team.
Chambers' victory in Birmingham would normally mean he would be guaranteed a place on the plane to Beijing, but a BOA by-law prevents the former drugs cheat competing at the Olympics.
It is this ruling that the 30-year-old is challenging in the High Court, with Craig Pickering and Tyrone Edgar left waiting to see if they will be included in the squad.
Dave Collins explains the selection decisions
Pickering, who finished third in the trials, and fourth-placed Edgar have clocked the required mark of 10.21 this season and are the two most likely to go to Beijing if Chambers is not successful.
If the High Court grants an injunction against the sprinter's lifetime Olympic ban for drug offences, selectors would be forced to pick the Londoner, meaning Edgar would probably miss out.
"We've gone with the athlete who is eligible and that's Simeon," UK Athletics performance director Dave Collins told BBC Radio 5 Live.
"Craig Pickering has made a strong case for himself. He's 2-0 with Tyrone Edgar. But then there's a chap called Marlon Devonish that might have something to say, while Harry Aikines-Aryeetey has run faster times than Craig."
Christine Ohuruogu ran in the 200m at the British trials in Birmingham
Triple jumper Phillips Idowu will go to Beijing as Britain's best medal hope in athletics after the 29-year-old landed the longest jump in the world this year at the trials with an effortless 17.58m on his first attempt.
Christian Malcolm secured his Olympic place with victory in the 200m; Alex Nelson will join the Welsh sprinter in Beijing, while Devonish claims the final spot despite withdrawing from Birmingham because of illness.
Paula Radcliffe had already been named in the team for the women's marathon even though her participation in Beijing is in doubt because of a stress fracture in her left thigh.
Athletes can drop out at any time on medical grounds and can later be replaced, which could mean Radcliffe leaving it as late as the night before the marathon on 17 August to decide whether she is fit enough to run.
Seven weeks ago specialists questioned her chances of being fit and Radcliffe has admitted she faces a race against time to be fit.
Andrew Steele pulled out of the 400m final but is named in the team, along with Martyn Rooney who kept up his unbeaten run over the distance this season by winning the British crown n 45.31 seconds.
World 400m champion Christine Ohuruogu tuned up for Beijing with second place in the 200m. She will be joined on the women's 400m team by Lee McConnell and Nicola Sanders, who took silver in Osaka.
Tasha Danvers gets the nod in the 400m hurdles ahead of Perri Shakes-Drayton, who beat Danvers in Birmingham at the weekend. However, the 19-year-old does not have the Olympic qualifying time.
"We've got published selection criteria and Tasha Danvers has ticked three of the four boxes," Collins told BBC News 24.
"She was second in the trials, she has multiple A standards and a record of being in top eight in world and Olympic competitions.
"It would go against our selection criteria not to pick her."
GB Athletics squad for Beijing:
100m: Simeon Williamson 200m: Marlon Devonish, Christian Malcolm, Alex Nelson 400m: Martyn Rooney, Andrew Steele 800m: Michael Rimmer 1500m: Andy Baddeley, Tom Lancashire 5000m: Mo Farah Marathon: Dan Robinson 110m hurdles: Andy Turner High jump: Germaine Mason, Tom Parsons Pole vault: Steve Lewis Long jump: Greg Rutherford, Chris Tomlinson Triple jump: Phillips Idowu, Larry Achike, Nathan Douglas Decathlon: Daniel Awde 4x100m: Harry Aikines-Aryeetey, Tyrone Edgar, Craig Pickering, Simeon Williamson 4x400m: Michael Bingham, Richard Buck, Martyn Rooney, Andrew Steele, Rob Tobin
100m: Jeanette Kwakye 200m: Emily Freeman 400m: Lee McConnell, Christine Ohuruogu, Nicola Sanders 800m: Marilyn Okoro 1500m: Lisa Dobriskey 5000m: Jo Pavey 10000m: Jo Pavey, Kate Reed 3000m steeplechase: Helen Clitheroe, Barbara Parker Marathon: Paula Radcliffe, Mara Yamauchi, Liz Yelling 400m hurdles: Tasha Danvers Pole vault: Kate Dennison Long jump: Jade Johnson Discus: Philippa Roles Javelin: Goldie Sayers Heptahlon: Kelly Sotherton 20k walk: Johanna Jackson 4x100m: Emma Ania, Montell Douglas, Jeanette Kwayke, Anyika Onuora, Laura Turner 4x400m: Lee McConnell, Christine Ohuruogu, Nicola Sanders
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