David Carry scooped a second gold of the day for Scotland with a brilliant win in the men's 400m freestyle.
Carry's win was Scotland's second gold in the pool
Carry, 24, held off a late challenge from Canada's Andrew Hurd to win in a time of three minutes, 48.17 seconds.
Welshman David Davies led after 200m, but faded slightly in the later stages to take the bronze.
Meanwhile, Liam Tancock almost broke the 50m backstroke world record in qualifying fastest for the final while fellow Englishman Matt Clay qualified.
"To have done something like that in this kind of environment is incredible - it's the stuff dreams are made of," Carry told the BBC.
Davies, who favours the longer 1500m discipline, felt he wasted a great opportunity to win gold.
He said: "I went out hard and thought I could have gone a bit quicker, but the legs faded a bit at the end.
"But it's not my main event so I'm pleased to win a medal. I've set a new personal best and a Welsh record so I can't complain too much."
Carry's triumph followed fellow Scot Caitlin McClatchey's victory in the women's 200m - the first swimming final of the Games.
Australia have traditionally dominated the men's 400m, but finished out of the medals after world record holder Ian Thorpe and reigning world champion Grant Hackett both withdrew from the Games.
Craig Stevens, who was called up last week when Thorpe pulled out due to illness, finished fourth.
Aberdonian Carry returned to the pool to anchor Scotland's 4x100m relay team but they could only manage fifth, one place behind England.
World record holders South Africa held off Australia in a thrilling finish to take gold, with Canada in third.
Moss Burmester, of New Zealand, took gold in the men's 200m butterfly in a Games record of one minute, 56.54 secs.
Australians Travis Nederpelt and Joshua Krogh took silver and bronze.
England's Matthew Bowe was sixth and Ian Powell of Guernsey finished eighth.