"I was on the high bar, did a dismount, got lost in the air and landed on my head," the 2012 European junior all-around champion says. "It was quite a hard surface so the physios and doctors knew straight away that I couldn't have fallen from that height and not be injured so they sent me to hospital. After I'd been for a scan and slept overnight, waking up the next day was pretty painful because I couldn't move properly. My head had swollen and I had two black eyes - it looked like I'd been in bar fight."
In the months since, the 18-year-old has faced the formidable task of defying the odds to return to full fitness. "It's always hard having time out of the sport," he says. "I was in a back brace for six weeks and wasn't allowed to do anything. After eight weeks I was able to start some basic training."
Even in those early days there was no doubting his determination."I wanted to get back into the gym so my coach brought in an exercise bike which was about 30 years old and I kept up my leg fitness up on that," says Baines. "I've actually found that since then my floor routines haven't been as tiring on my legs, so there's a silver lining to every dark cloud."
Helping his focus has been the goal of competing at the 2014 Commonwealth Games in Glasgow. Among the most prodigious talents to have come out of British Gymnastics in recent years, Liverpool-born Baines, who has a Scottish father and English mother, has found himself in the enviable position of having two nations vying for his allegiance, but he has now officially pledged himself to the ranks of Team Scotland.
"There were three main reasons," Baines says. "The first was that [training partners] Daniel Purvis and Daniel Keatings both compete for Scotland already. They convinced me that it would help further Scotland's chances of getting a medal at the Commonwealth Games.
"I realised too that Glasgow 2014 will be in front of a home crowd. I went to the 2012 Olympic Games in London and watched the [Team GB] lads get the bronze medal in the team final and saw what a difference that home crowd made to morale. It would be amazing to compete in Glasgow and replicate that feeling.
"My dad was born in Inverness and grew up in Balmullo, a tiny village in Fife. When I was younger I spent a lot of time in Scotland. Whenever I had holidays that's where we'd go, mostly to St Andrews where my grandma lives. I have tons of great memories of lying on the beach and eating ice cream."
On Saturday, Baines will be back in action for the first time since his accident, at the senior all-around title at the Scottish National Gymnastics Championships in Perth. He will go head-to-head with Purvis, who was part of that Olympic bronze-medal-winning GB team; reigning European pommel horse champion Daniel Keatings; and the current holder of the Scottish all-around title, Adam Cox.
Baines' injury has meant he hasn't had the opportunity to pursue the qualification standards for Glasgow 2014. While Sunday Herald columnist Cox has tipped Baines as a leading contender for a Team Scotland spot, the man himself is reticent to get too far ahead of himself.
"It's nice to hear that and a real confidence boost, but I still need to get the qualification scores," says Baines. "An all-around medal would be the aim because I have Purvis and Keatings to compete against. They are good friends but it would be nice to challenge them for the overall title. I've been back training on all six pieces of apparatus since the middle of December. It's been tough but I'm getting there and hopefully I'll get a good result that will show I've recovered well."
The second eldest of four brothers, Baines was a late arrival to gymnastics at the age of nine. "My mate taught me how to do a backflip on the trampoline," he says. "I'd always had a lot of energy but when I started doing flips with my eyes closed, my mum and dad decided it was probably a good idea to take me somewhere that I could be taught properly."
Baines has been a dominant force in the British rankings over the past six years, a former all-around champion at both under-14 and under-18 level. He took gold on the parallel bars and silver on floor at the 2011 European Youth Olympics.
Having recently made the step up to senior level, Baines is coached by Jeff Brookes at Southport YMCA and Andrei Popov at the British Gym- nastics HQ in Lilleshall. He admits there is a friendly rivalry between the Scots - himself, Purvis and Keatings - and English gymnasts such as Kristian Thomas, Max Whitlock and the recently-returned Louis Smith ahead of this summer's Games.
"When we are doing our pommel routines it's always a competition to see how many of us from Scotland will beat the guys from England," he says. "It's good fun and I think Andrei quite enjoys it too because it makes us all work harder."
o The 2014 Scottish National Gymnastics Championships is at Bells Sports Centre, Perth, February 22-23