The double-Olympic champion swimmer Rebecca Adlington has made it through to the next round of the 800m freestyle.
The British number one has already won a bronze in the 400m event after and she put in a strong swim in the longer swim to finish the heats in the lead position with a time of eight minutes and 21.78 seconds – just ahead of Denmark's Lotte Friis.
Five-time Olympian Mark Foster praised Becky's team spirit and told BBC Sport: "What is quite charming about Becky is that she doesn't know how good she is. She talks about others. She loves the whole team environment and taken the role of leader.
"She gets a buzz off what everyone else can do. I think Becky might have to be at her best and that might mean breaking the world record."
She will return to the pool today to defend her title and is expected to be watched by a sell-out crowd.
Meanwhile, US swimmer Michael Phelps claimed the 16th Olympic gold medal of his career and 20th medal in total after winning the 200m individual medley in front of a crowd, with many staying at central London hotels.
The record-breaking athlete also explained that a famous American back home has been supporting and enjoying the London 2012 Games.
Phelps explained to BBC Sport: "The president of the United States Barack Obama called me on Wednesday. It was pretty cool.
"Someone called me up and asked me to hold on as they had the president waiting to speak to me. He told me that everyone is supporting me. It was very special and he said to say hi to my mum."