Glasgow-born Jamieson, who won silver at the Delhi Games in 2010 and at the 2012 London Olympic Games, had been hotly tipped to win the first gold medal of his career but had to settle for another second-place finish after an astonishing swim from Murdoch.
The 20-year-old could barely believe his career-best time of two minutes 7.30 seconds, a British record, and stared open-mouthed at the digital display board following the race.
Andrew Willis of England narrowly secured the bronze medal in a blistering final that was accompanied by deafening cheers from the partisan crowd.
"There is no way that just happened," Murdoch told the BBC.
"In the last 100m the sound was just amazing and it drove me on. I felt really good this morning in the heats but I didn't believe that I could do that. It is my granddad's 70th birthday so that is for him."
Each Scottish swimmer was met with rapturous cheers during the evening session at the Tollcross Swimming Centre and the vociferous support was converted into medal-winning performances.
Hannah Miley ensured Scotland got off to a winning start when she took the lead on the last turn of the 400m individual medley final from England's Aimee Willmott to snatch the first gold of the evening with a new Games record.
"It was a great race between me and Aimee," Miley said. "I had to dig deep and we pushed each other on to good times.
"It was fantastic to set a personal best here. The crowd were pretty cool. When I walked out I had my headphones on and it was hard to stay in that bubble and drown out the crowd."
Canada's Ryan Cochrane, who took silver at London 2012, took the next gold in similar fashion, timing his charge perfectly to touch first in the 400m freestyle.
Games records continued to tumble as Emma McKeon edged to 200m freestyle gold in a record time, securing Australia's first medal in the pool.
England's 18-year-old Siobhan-Marie O'Connor was just a quarter of a second behind in second.
The evening ended with Australia smashing the women's 4x100m freestyle relay world record by nearly a second to take gold, but the day belonged to Scotland's new golden boy Murdoch.
He will renew his rivalry with Jamieson when the 100m breaststroke competition gets underway on Friday.
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