ROSS Murdoch upset the odds as he pipped Michael Jamieson, the face of Glasgow 2014, to making it four golds for Scotland on a glittering day in the Commonwealth Games.

On what was dubbed Thunder Thursday, the day when Scotland's athletes were expected to explode onto the Games stage, they did so - big time.

The Balfron star's success in the 200m breaststroke followed that of Hannah Miley, who twice smashed her own Commonwealth Games record in the 400m individual medley to win Scotland's first gold of the night in the pool.

The 24-year-old Miley broke down in tears on the top step of the podium at the Tollcross International Swimming Centre as a piper played Flower of Scotland after she successfully defended her gold medal from Delhi.

Murdoch, 20, left Jamieson to settle for silver, and dedicated the win to his grandfather, who was celebrating his 70th birthday.

"There's no way that just happened," he said. "I can't believe it. That was amazing, it's a dream come true.

"It was a massive personal best for me. I didn't think I could do that if I'm honest. I'm so surprised."

Scotland's newest sporting hero even had an Andy Murray-style moment. TV cameras caught him using a four-letter word to describe his shock after he turned round, wide-eyed in amazement at his result, which set a new Commonwealth record with a time of two minutes and 7.3 seconds.

Murdoch quickly realised what he had said - which it was not picked up by microphones - and covered his mouth up.

He tried but could not prevent the tears as he stood proudly on the winners podium with his gold medal as the Glasgow venue resounded to the sound of Scotland's national anthem.

After the home team rocked arm in arm to Flower of Scotland, they created a guard of honour for Murdoch as he showed off his medal to the excited audience.

In the immediate aftermath of Murdoch's win, Jamieson fans who had bedecked the stands with home-made banners willing the Olympic silver medallist to win seemed stunned.

The tension before the final even amongst spectators was almost tangible as Murdoch, Jamieson and Edinburgh's Calum Tait all lined up to take the plunge. Eardrums stung from the deafening cheers as all three were introduced.

The noise was replaced by an eerie anticipatory hush as the swimmers stood on the blocks, soon converted to a release of rousing cheers and Saltire waving at a jam-packed Tollcross Swimming Centre.

Like the ACDC song which blasted across the pool some 15 minutes earlier, the crowd were thunderstruck as Scotland plundered its third gold in three amazing Glasgow 2014 hours - from an unexpected source.

It appeared the tension that Glasgow 2014 poster-boy Jamieson spoke of in an earlier heat, had caught up with him and it was Stirling's Murdoch who stormed to victory.

Jamieson had gone into last night's final as second-fastest from the earlier afternoon heats behind Murdoch.

After he spoke as if his career has been destined for this defining moment, some wondered whether he had heaped far too much pressure on himself.

The Glasgow-born breaststroke specialist was the class act in the field on paper, being the only swimmer in the world to go under 2mins 8secs this year.

But it was Murdoch who came close to breaking the world record, coming just 0.29 seconds behind the mark set by Japan's Akihiro Yamaguchi.

The crowd were ecstatic as the medallist paraded around the pool. Stanley Harvey, 40, with his children, Kim, 4 and Richard, 6, both proudly displaying Saltire painted faces, said: "It was incredible. I have never encountered an atmosphere like this at any event I have been to and I am a Celtic season-ticket holder.

"I would have been overwhelmed to see any of our boys get gold, and it was gold and silver, amazing."

Mary Aitchison, a 58-year-old receptionist was waving her Saltire frantically and was overcome with emotion.

"I've never been to any swimming event before and this was just wonderful," she said. "I am so proud to be Scottish."

Fans tweeted their congratulations with Sarah Atkin saying: "A star is born - what a race."

Ross Bergmann wrote: "Does it really matter that #RossMurdoch didn't read the script? @Team_Scotland 1&2 will have to do."

There was joy earlier, but without the shock, after Miley beat England's Aimee Willmott in 4min 31.76secs. She wrapped herself in a Saltire and hugged her tearful mother and two brothers in the stands, then went on a lap of honour.

Miley, of Inverurie, Aberdeenshire, thanked the noisy fans. She said: "I tried to drown out the noise a little bit before the race, but it was really great and helped me both tonight and in the heats."

Seven-time Olympic gold medallist Sir Chris Hoy tweeted: "Gold for Hannah Miley in the pool!!" TV presenter Gabby Logan, married to former Scotland rugby international Kenny Logan tweeted: "First tears in the Logan house thanks to @HannahMiley89 you had us all going including @KennyLogan - amazing swim and beautiful reaction.

Team Scotland tweeted: "She came, she saw, she conquered. Scotland's first gold."

Lewis Wilson tweeted: "Well done Hannah Miley. I'd be blubbing my face off too."

Scotland's Stephen Milne, Dan Wallace and Robbie Renwick missed out on medals in the men's 400m freestyle.