Playing his club rugby for Gala, Heriot's and currently with West of Scotland, the 22-year-old featured for the Border Reivers and Glasgow Warriors' back-up team before making his debut with Edinburgh during the home win over Ulster in January.
Now the Botswana-born forward says he is thrilled to have achieved his lifelong dream; to become a professional rugby player in Scotland.
Grant said: "I'm obviously delighted; it is one of the best feelings I think I've ever had.
"I've always wanted to play professional rugby in Scotland, so to finally get the offer is brilliant.
"I've been involved as an apprentice in the Academy set-up for the past three years, so it's great to finally see all that hard work come off. I'm looking forward to being involved with Edinburgh next season.
"At the start of the season, I was affiliated to Glasgow and I moved to play for West of Scotland. I was working hard there and playing in the back-up games for Glasgow.
"But luckily enough for me because I was part of the National Academy I was able to move between the two professional teams and I was fortunate enough to get an opportunity with Edinburgh because of injuries.
"My first goal was always just to play professional rugby in Scotland and that has happened with Edinburgh."
After being awarded the John Macphail Scholarship in 2008, Grant spent last summer playing for Auckland University club in New Zealand and he has since captained Scotland 7s; steps he believes have helped him become an Edinburgh player.
He added: "The experiences in New Zealand and with Scotland 7s have been invaluable and it has helped me to mature as a rugby player.
"Scottish Rugby have been fantastic with me. They have persisted with me - even when I injured my knee. I believe I have progressed and grown as a player and it has been brilliant building towards the contract."
Grant admits one aspect he is really looking forward to next season is the prospect of working with Edinburgh head coach Andy Robinson on a daily basis.
He said: "Working with Andy in the build-up to the Ulster game was brilliant. Before the game, I picked up lots of tips from him and afterwards we went through the video analysis together one-on-one.
"He definitely opened up my eyes towards the way I play and reviewing games. He made me look at parts of my game that I wouldn't have even thought about before.
"The fact that he played in my position as well will be brilliant for me as a player."
Ahead of next season's challenges at Murrayfield, Grant says he is excited about the possibility of appearing at the home of Scottish Rugby in the near future when Scotland hosts the Emirates Airline Edinburgh 7s Festival on 30 and 31 May.
He said: "Playing at Murrayfield - the home of Scottish Rugby - is always really exciting. Hopefully I will get that opportunity in May and next season with Edinburgh as well.
"Playing for Scotland at home is something really special. In terms of my own development, I really want to lay down a benchmark and build up some momentum heading into next season."
National Academy manager and Scotland 7s head coach Stephen Gemmell backed Grant's elevation into the professional ranks and he believes the player will make an impact with Edinburgh.
He said: "Roddy is a huge asset for every team he has played for; he has got a tremendous attitude and a great work-rate.
"He has worked really hard to get to where he is. Roddy has been a very consistent player for us on the international 7s stage and I'm sure he will make an impact in the Magners League, Heineken Cup and hopefully beyond that."
Roddy will be on board for Edinburgh's next campaign and the club's supporters can follow suit by signing up for 2009/2010 season ticket packages with the details set to be released on Friday (17 April) at Murrayfield before the Leinster match.
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