The leap from junior to senior ranks happens quicker than ever these days. The academy structures and improved conditioning help talented youngsters break through quickly; if you’re good enough, you’re old enough.

Among the prodigious talents who made the grade at a young age are Jonny Wilkinson (18 years old when first capped), Dan Carter (21), Brian O’Driscoll (20), Schalk Burger (20) and Imanol Harinordoquy (21).

Ian Gilbert selects a magnificent seven whom we can expect to see more of at Test level.

Elton Jantjies is already well known to South African crowds after a 2011 season that plumbed the depths and hit the heights.

The fly half played in a wounded Golden Lions team that finished the Super Rugby season second from bottom. Later in the year, however, the 21-year-old steered the Johannesburg-based outfit to the Currie Cup title, kicking 24 points in the final against the Sharks.

Jantjies came through the Under 20 set-up and toured with the Springboks in 2010 without claiming a Test cap. Full honours must come sooner rather than later.

If interim England coach Stuart Lancaster needs an unflappable kicker to replace Jonny Wilkinson, 20-year-old Owen Farrell might be the man. The fly half cum centre landed 17 points to help Saracens seal the English Premiership title earlier this year against Leicester Tigers at a packed Twickenham.

Farrell’s rugby lineage is impeccable – his father Andy, the rugby league legend who finished his career in union with England and is now on the national coaching team.

Centre Robert Lilomaiava was one of the star turns at the IRB Junior World Rugby Trophy 2011 in Georgia, helping Samoa win the title and promotion back to the Junior World Championship for 2012. His nine tries set a record for either tournament, beating the eight of New Zealand’s Zac Guildford and Julian Savea, who have gone on to full and Sevens honours respectively.

Lilomaiava has forced his way into the national Sevens side – playing the first three rounds of the 2011/12 HSBC Sevens World Series in Gold Coast, Dubai and Port Elizabeth – and is still eligible for JWC 2012 as he turns 20 only in March.

The prospect of facing Australia’s Faingaa twins, Saia and Anthony, is daunting enough, but international defences may soon have a third brother to worry about. Colby, a flanker, impressed observers at JWC 2011 with his powerful running and presence at the breakdown. The 20-year-old already has a couple of years’ Super Rugby under his belt with the ACT Brumbies – his brothers’ side before they moved to the Queensland Reds.

There must have been something special in the porridge at the Whitelock household; the Christchurch-based Crusaders feature brothers George, Adam, Sam and now youngest sibling Luke in their Super Rugby squad.

Sam is already a Rugby World Cup winner and 20-year-old Luke – already touted as a future All Blacks captain – led his country to the JWC title in 2011, picking up his second winners’ medal having also played in 2010. The loose forward was also nominated for IRB Junior Player of the Year 2011, but missed out to England's whizz kid George Ford. 

Jean-Marc Doussain plays scrum half for leading French side Toulouse but at JWC 2011 he dictated matters from fly half. Aged 20, Doussain made his Test debut as a replacement scrum half in the dying minutes of the Rugby World Cup 2011 Final in Auckland. Named the Top 14 Young Player of the Year in 2011, commentator Nigel Starmer-Smith – a former international No 9 himself – called him “le petit general” during JWC 2011.

Another player who has already made the leap to senior action is Russia’s 192cm-tall wing cum full back Denis Simplikevich, who turns 21 in March. Having impressed at Under 20 level in the Junior World Rugby Trophy in 2010 and 2011, he was fast-tracked into the senior side for their first ever Rugby World Cup and duly marked his debut with a try against Ireland.

Another followed against the Wallabies and expect the Siberian speedster to figure prominently in the climax of the European Nations Cup 2012, which runs parallel to the Six Nations.