Having been far from a certainty for the initial 37-man party, Roberts had been widely viewed as a utility back prior to travelling to South Africa.
The Cardiff Blues powerhouse had already played full back, wing and centre for Wales by the time Sir Ian McGeechan picked him for Britain and Ireland's elite.
But his time with the Lions saw him established in midfield - a position that he has filled for club and country ever since.
Roberts was named HSBC Player of the Tour as his combination of graft and guile earned him a Test start in both the first and second internationals against the Springboks.
But a wrist injury cruelly robbed him of one of the most treasured experiences in the sport - a Test win with the Lions.
Roberts was left to watch from the sidelines as McGeechan's men destroyed the Boks in the third and final Test and, although he was delighted with the 24-9 win in Johannesburg, Roberts admits he was heartbroken not to play his part.
"One of my stand out memories of the tour is getting injured and not being part of the third Test. I was really gutted not to be involved in that," said Roberts of the Lions first Test victory since 2001.
"The boys didn't need much motivation and I certainly had a tear in my eye seeing guys like Simon Shaw, Stephen Jones and Martyn Williams win a Test match for the Lions.
"When I got picked it was certainly a life changing moment. I was one of the inexperienced guys out there but half way through I found myself in the Test team.
"Running out for the first Test match was such a contrast. The first game against the Royal XV was the same weekend of the Super 14 Final. We were in a huge empty stadium and it was a bit of an anti-climax.
"But the first Test in Durban was incredible. There is nothing else like it as a player. It is like running out in the Collosium as a gladiator. You expect it to be a sea of green. But it was full of people in red following us."
Jamie Roberts played the first and second Tests but missed the third
One of the individual success stories of the tour, Roberts was also praised for his partnership with Brian O'Driscoll.
Roberts combined with the legendary Irishman to form a centre partnership that many believe has no equal in the global game.
The Welshman's ability to put the Lions on the front foot regularly gave O'Drsicoll the chance to cause havoc, while the Ireland skipper's quick feet constantly kept defenders guessing and allowed Roberts the time and space to charge forward.
For Roberts himself, playing alongside the legendary Lion was a truly magical experience and one that only really sunk in once he returned home from South Africa.
"To have that partnership was incredible," added Roberts.
"I don't think I realised at the time how much I learnt from Brian until now. He's a guy who has played for Ireland 100 times and gone on three Lions tours. He's certainly someone you admire.
"I used to watch him as a 15-year-old. To get the chance to play with him at the highest level is certainly one of the highlights of my career.
"It's important to mention Stephen Jones at 10 as well. As a young guy having Brian with 90-odd caps and three Lions tours the one side and the other Stephen with two Lions tours and 90-caps made my job so much easier and accelerated my learning curve. I was comfortable from day one."