Gold Coast - Hosts Australia produced two astonishing relay fight-backs on the final night of the Commonwealth Games swimming Tuesday as Canadian teenager Taylor Ruck bagged a record-equalling eighth medal.
Olympic champion Kyle Chalmers mowed down England's Ben Proud on the final leg, the freestyle, as the Aussies won an absorbing 4x100 metres medley relay to finish with 21 gold medals on the Gold Coast.
READ: Chad, Cameron add to Team SA medal tally
Chalmers stopped the clock in a Games-record three minutes, 31.04 seconds, just seven-hundredths ahead of Proud, who led at the turn after strong legs from Adam Peaty and James Guy, but just ran out of steam.
The women's medley relay was every bit as close, Canada's teen sensation Ruck turning for home on the anchor leg almost half-a-second in front, only to be pipped by Bronte Campbell as Australia won in 3:54.36.
"We watched Bronte come over the top of the other girls in that women's race, so I knew that I wanted to do the same thing," said Chalmers. "To do it with these boys is awesome."
Ruck, who prepares for races by drinking espresso, equalled countryman Ralph Hutton and Australian swimmers Susie O'Neill and Emily Seebohm for the most medals captured at a single Commonwealth Games - but apologised for being too young to know who O'Neill was.
"I'm just so honoured to win that many medals," Ruck told AFP. "I don't think it's sunk in yet and I don't know when it will."
Australia won six of Tuesday's seven finals as they preserved a Commonwealth Games win streak in swimming that stretches back to Edmonton in 1978.
Jack McLoughlin crushed fellow Aussie Mack Horton to win 1 500m freestyle gold, denying the Olympic 400m champion a Games hat-trick.
McLoughlin's clocked 14:47.09 to beat Welshman Daniel Jervis and Horton as Australia won the event they used to dominate for the first time since Grant Hackett's 2002 victory in Manchester.
Mitch Larkin won the 200m individual medley final in 1:57.67 and, having already completed the backstroke treble, ended the Games with five gold medals after leading off the 4x100m medley relay.
Scotland's Duncan Scott, who produced arguably the swim of the Games to win the blue riband 100m freestyle at the weekend, took silver for his sixth medal of a breakout meet.
Australian teenager Ariarne Titmus bagged her third gold medal by romping to victory in the women's 400m freestyle in a Games record of 4:00.93 - and won an unusual bet she made with coach Dean Boxall.
"Dean said if I won, he would get his hair in braids so I'm really excited," said the Tasmania-born teenager. "He said if I went under four minutes, he would shave his head -- we will save that for another time!"
Rain begun to thunder down just before the women's 50m backstroke final, won by Seebohm, who touched just four-hundredths before treble-chasing Kylie Masse of Canada.
Proud retained his 50m freestyle crown as he held off South Africa's Bradley Tandy to win England's sixth swimming gold in 21.35, making up for last week's disqualification in the 50m fly.