Bromley's Ellen Gandy during the 100m butterfly final Tim Ireland/PA Wire

by Alex Hoad at the Aquatics Centre

Ellen Gandy was in tears after sensationally exiting the 200m butterfly in the heats at the Aquatics Centre on Tuesday morning, potentially ending her Olympic Games.

The 20-year-old Bromley star had been a British hope for a medal in her strongest event, having claimed a silver in last year's World Championships in China.

However despite leading for the first three lengths of the 200m race on Tuesday, she appeared to hit the wall 60m from home.

Gandy led by a fraction of a second at the final turn but was overtaken by four rivals on the way in and finished fifth in a time of 2.09.92 - some five seconds outside her personal best.

Gandy was through 150m in a time of 1.34.31 but then swam 35.61 over the final 50m to finish well adrift of heat winner Liuyang Jiao, who took gold in the World Championships ahead of her.

Gandy admitted later: "I felt okay at the start but after 100m I felt like I had been hit by a truck. I've been feeling fine, no health issues, I just don't know what happened."

The former Balgowan School, Beckenham, and Langley Park Grammar School pupil - who swam at Beckenham SC before moving to Australia with her family aged 17 - missed out on the top-16 and the semi-finals by 0.59 seconds.

She could yet compete in a relay for GB.