The 22-year-old came through the ranks at Gala and made his debut for the first XV at Netherdale when he was just 17.
Impressive performances for the Maroons, including the Scottish Cup final win over Ayr in 2011-12, alerted Edinburgh to his rising potential and last summer the professional outfit signed him up on an elite development player (EDP) contract.
When not required for Edinburgh last season, McQuillin was turning out for Gala but this season, when this is the case, will be playing his club rugby for the Greenyards club in the BT Premiership.
McQuillin has been in New Zealand this summer on the John Macphail Scholarship and Melrose head coach John Dalziel is delighted that he may be able to call on him in the coming months.
Dalziel, himself a former Gala and Melrose player, said: “As he is in the EDP programme with Edinburgh and is wanting to make it as a pro player, we hope that Ewan can force his way into their squad.
“However, if and when he is available to play for us I am sure he will bring a lot to our squad. We were asked if we would be keen to have him here, and after speaking to Ewan, I am pleased that he will be with us this season. He has come on really well in the last couple of years, has played for the club international side and is training full-time so he is an exciting prospect.”
The move has set tongues wagging in the Borders with the rivalry between Melrose and Gala having always been in the air, while last season the former pipped the latter to the top-flight title on a dramatic final day.
Both clubs are expected to challenge for the title again in the BT Premiership in 2014-15 and the news of McQuillin’s move may add extra spice to the next meeting between the two on 18 October.
Melrose got their pre-season campaign underway at the weekend with a training match against Watsonians and that preparation moves up a notch with a Border League match against Selkirk on Saturday before the new BT Charity Shield against Ayr the following week.
The league matches begin on 30 August when they take on Edinburgh Accies and Dalziel is excited about some of the other new faces he has brought in addition to McQuillin.
They include former Scotland Under-20 scrum-half Murdo McAndrew, fresh from a spell in France with Clermont Auvergne, and Dalziel is looking forward to seeing how he and fellow number nine Tom Wilson get on.
“Murdo has looked great in pre-season and he has a real buzz about him and is excited to be here. He played really well against Watsonians and he and Tom, who did well last year, will push each other on.”
McAndrew’s arrival is particularly welcoming given that Bruce Colvine is still playing out in New Zealand along with Grant Runciman.
In the back row, Neil Irvine-Hess, who was an Edinburgh EDP last term, has arrived from Watsonians and is coming off the back of the IRB Junior World Championships in New Zealand. Second-row Lewis Carmichael, impressive last season, is doing likewise and it will be interesting to see how they progress in the coming weeks and months.
Australian hooker Todd Pearce is set to return to the club soon and next week a winger from the same country is set to arrive to bolster the back-three options.
Last year’s captain, Fraser Thomson, who only played a handful of matches because of injury, is now back to full fitness and having him available will also be a big boost for Melrose.
Dalziel concluded: “I am pleased with the way things are coming together. The players have been working hard in pre-season and I think we have a competitive squad. The Watsonians training game was very useful and it will now be good to get two tough matches – Selkirk and Ayr – under our belts before the league proper starts up.”