Geoffrey Andrew Huegill (born 4 March 1979) is an Australian butterfly swimmer who won silver in the 4×100 metre medley relay and bronze in the 100 metre butterfly at the 2000 Summer Olympics in Sydney. He held the long course world record in the 50 metre butterfly from 2000 to 2003.
Huegill attempted to qualify for the Australian team at the 2005 and 2006 Australian championships, however, he was unsuccessful. After retiring from competitive swimming, he went on a downward spiral taking drugs, and suffering severe depression. In 2007, he met publicist Sara Hills, who Huegill credits with turning his life around. They married in 2011 and conceived their first child unexpectedly on their honeymoon. Their daughter, Mila, was born in January 2012.
On 12 November 2008, Huegill announced his comeback to competitive swimming. Having had major battles with his weight since quitting the sport following the 2004 Athens Olympics. He said he had lost more than 40 kilograms (coming from 138 kg) for his comeback and would train for the 50 and 100 butterfly with the aim of competing at the 2010 Delhi Commonwealth Games. He sparked attention of the Australian sports media by qualifying for the finals in the 50 and 100 metre butterfly at the 2009 Telstra Australian Championships (being interviewed after every swim). He built more momentum in August 2009 at the Australian Short Course Championships, capturing his first national medal in 5 years.
2010 brought enormous improvements, clocking 23.44 in the 50 metre butterfly to win the Australian title, just 0.02s off his old world record from 2001. His 100 metre butterfly was 53.09 seconds, finishing 5th. In a post-swim interview he claimed to be a lean 93 kg. At the 2010 Pan Pacs he clocked 23.27 seconds in the heats of the 50 metre butterfly but was not able to back up that form in the finals, finishing just outside the medals. His 100 butterfly was 52.21, his second-fastest time ever, faster than his bronze medal swim in Sydney almost ten years before. He picked up a bronze medal in the medley relay. At the 2010 Delhi Commonwealth Games he won gold medals in the 4×100 metre medley and the 100 metre butterfly breaking a ten year-old personal best when winning in 51.69 seconds (Commonwealth games record). He was narrowly beaten by 0.02 of a second in the 50 metre butterfly by Kenyan Jason Dunford in a time of 23.37. Huegill swam at the 2010 FINA World Swimming Championships (25 m), no medals were achieved however he did earn his name back into the record list with an Australian record the 4×100 metre medley relay.
During a media conference at the Bondi Icebergs Club pool on 21 January 2011, Huegill announced his intention to compete at the 2012 Summer Olympics. Unfortunately he narrowly missed out on the team coming in fifth in the 100 metre butterfly finals at the 2012 Australian Swimming Championships in Adelaide, South Australia with 52.50 seconds