ONE is a reigning Commonwealth champion, the other is barely into her teens, yet there is a rare symbiosis between Hannah Miley and Erraid Davies as they prepare to make waves in Glasgow.

Both these swimmers were at the Aberdeen Aquatics Centre yesterday, brimming with excitement and anticipation about what the next few weeks will bring and it was difficult not to be swept along on their tidal force of joy.

Miley needs no introduction, of course, as one of Scotland's greatest-ever performers in the pool, and she was typically bubbly, loquacious and analytical - "I tend to waffle a lot" - while telling us how her preparations were going.

A few feet away, Davies, who was born in Dundee but is now living in Shetland, gazed reverentially at her compatriot and you could almost see the wheels going round in her head. At just 13, she is the youngest-ever competitor in Scotland's Commonwealth Games history, but she lapped up the media attention, took some tips from Miley on the art of unveiling a snappy soundbite, and generally looked as if somebody had handed her the keys to a candy store.

The duo have contrasting expectations, with Miley striving to defend her 400m individual medley title, and para-sport swimmer Davies making her debut at this exalted level in the 100m breaststroke. Yet these differences don't mask their ambition, nor dedication to their jobs.

"I have only got half a hipbone in my left hip," the youngster explained. "I didn't tell some of my classmates I was going to be involved in the Games, but then I carried the baton [at the Queen's Baton Relay in Shetland] and everybody knew what was happening. It has been really good. My mum came down with me to Aberdeen and my aunt and uncle managed to get tickets, so I think there will be lots of support when the Games begin."

Miley, for her part, is continuing to excel on a global stage. The 24-year-old suffered a dodgy few moments in Melbourne at the 2006 festival when she forgot her accreditation pass in the athletes' village and had to break into her room to retrieve it, but there have been no smash-and-grab jobs in the last eight years.

On the contrary, her record speaks volumes about the idiosyncratic fashion in which she and her father and coach, Patrick, have plotted a path from Garioch Aquatics Club in Inverurie to a variety of podiums at Commonwealth, European and World Championships.

It hasn't all been plain sailing. There were lachrymose scenes in the aftermath of Miley's displays during the 2012 London Olympics, where she reached finals but missed out on any medals. But, despite her diminutive stature, the 25-year-old is as fragile as a moose and has picked herself up with a flourish and a fistful of fresh honours. For her, age - and it is quite some time since hers was one of the younger names at the top of the world rankings - is merely a number. What counts is that she puts in the requisite graft to succeed.

"For me, this is just another competition, and while I know it will be very special to be at the Games, I am not preparing for it any differently to how I would get ready for a World or European Championships," said Miley, who swims in her specialist 400m on day one of the competition at Tollcross Park, next Thursday.

"That approach helps my nerves and puts thins in perspective. The first half of this season was tough for me, psychologically, and I had to sit down and talk to myself about what was happening.

"It was difficult. The hard work I was putting into training was not being reflected in my results and performances. But if you have been doing this as long as I have, you grow to recognise that swimming can be a very unforgiving sport.

"I am in a good place now, though, and I think I am pretty close to my best. You can feel great one day and rubbish the next, but I am where I want to be a week before the start."

These words apply equally to Davies, a member of the Delting Dolphins club, who has demonstrated a huge appetite for dragging herself out of bed and heading along to the only 25m pool in the Shetland Islands, come rain, snow or darkness.

"I've enjoyed being with the other swimmers in Aberdeen and we will be together all the way through to the Games," said Davies. "I get Saturdays off, but the rest of the time, I do as much as I can [with her coach Lorraine Gifford] and up to nine sessions a week."

Miley has shown the same relish for stakhanovite labour throughout the last decade and is not interested in calling it quits before the Rio Olympics in 2016. She did hint that she would savour passing on her experience to the next generation, particularly now a state-of-the-art aquatics centre has opened near to her roots. But that is in the future. For the moment, her steely gaze is focused purely on repelling any rivals.

"I am expecting to face a stiff challenge from [England's] Aimee Willmott, who was ahead of me in the rankings earlier this year, and I reckon she is one of the closest to me, and there are also a couple of Australian girls who could pose a threat," said Miley.

"But I can't control what they do once we are all in the water. I might do a personal best and it is only good enough for silver or bronze if somebody goes out and smashes six seconds off their previous best time. But that is just the way it is."

Miley does not indulge in bland platitudes. She is as driven now as she was at the 2006 Games and there is no doubt who provides the impetus and vital spark in her life.

"My dad has been a huge influence on me and he has been coaching me throughout my career, so it's good to be able to take him on the journey," said Miley. "It's because of him I am successful and I'll be the first to give him a hug [in Glasgow]."

Hannah and Erraid might be on different rungs of the ladder. But this redoubtable pair clearly share the philosophy that the only way is up.