"Crazy," said the affable Wales and Cardiff Blues centre, who is in just a second season of full-time professional rugby.

Roberts, by 12 months, will be the youngest British and Irish Lion to start Saturday's first Test against world champions South Africa.

But it is a richly deserved reward for a player whose midfield partnership with Ireland star Brian O'Driscoll has established itself among the tour's most effective combinations.

"It's pretty crazy, but brilliant at the same time," added Roberts, who only won the first of his 12 Wales caps during last year's RBS 6 Nations Grand Slam campaign.

"It's crazy it has come this early for me, but it has come at the right time. I have been playing well this season.

"It was my first game at 12 out here last summer when Wales played South Africa, and here I am finding myself playing in a Lions Test on Saturday."