SCOTLAND

Name: Finn Russell

Age: 23

Position: Stand-off

Club: Glasgow Warriors

Caps: 15

An exciting, exuberant talent, Russell is the key ingredient of the most potent Scotland back line for some years. A courageous player who unlike many fly-halves actually enjoys defending, he keeps the opposition - and occasionally his own team-mates - guessing because of his unpredictability when in possession.

ENGLAND

Name: Dylan Hartley

Age: 29

Position: Hooker

Club: Northampton Saints

Caps: 66

New coach Eddie Jones’s controversial choice as captain, Hartley has served a total of more than a year’s suspension. Any repeat of such indiscipline will jeopardise Jones’s whole plan for an England recovery, although a sainted Hartley could make a powerful contribution in the loose as well as the set piece.

IRELAND

Name: Jonathan Sexton

Age: 30

Position: Stand-off

Club: Leinster

Caps: 56

The experienced fly-half, back home this season after a couple of years in Paris with Racing, has a vital part to play in Ireland’s defence of their title. He missed their first match last year and was in danger of doing the same this year after a head injury against Wasps, but provided he plays he can be a vital stabilising influence.

WALES

Name: George North

Age: 23

Position: Wing

Club: Northampton Saints

Caps: 55

Criminally underused by his club, where the forwards prefer to do all the work themselves, North remains one of the most dangerous wingers in the game. Blessed with great natural strength, he is going into the Six Nations “in a really good frame of mind” after playing his best game yet for the Saints against Scarlets, according to club coach Jim Mallinder.

FRANCE

Name: Louis Picamoles

Age: 30 (on 5 February)

Position: Back row

Club: Toulouse

Caps: 51

The retiral of World Cup Thierry Dusautoir has left a big gap in the French back row, and the onus will be on Picamoles to fill it as well as compensating for the captain’s lost leadership. When France are at their best the plaudits often go to their backs, but Picamoles, who is bound for Northampton in the summer, has usually done the hard graft up front first.

ITALY

Name: Sergio Parisse

Age: 32

Position: No 8

Club: Stade Francais

Caps: 114

If Italy are to achieve anything in the tournament, they will need their captain to be fully fit - which was not the case during the World Cup - and on top of his game. The Argentine-born forward is a vastly experienced and inspiring figure and has been a key ingredient of most of his team’s successes in recent years.