Six Nations 2014: Foreign legion who took over the tournament

Scott’s a Scot: Coach Johnson today tries to outfox Joe Schmidt in Dublin

The influence of the interloper has never been more obvious than in this year's Six Nations' Championship. For the first time four teams have a foreigner as head coach, with Ireland's Joe Schmidt (a New Zealander) and Scotland's Scott Johnson (an Australian) facing off in Dublin today, while Wales's Warren Gatland (another Kiwi) comes up against Italy's Jacques Brunel (a Frenchman).

The trend, which began when the game went professional in the mid-1990s, is "inevitable", to quote Bernard Jackman, an Irish coach currently on the rise with Grenoble in the French league. France and England have never varied from indigenous head coaches, but Ireland, Scotland, Italy and Wales have regularly looked beyond their shores for help.

Gatland's success aside, foreigners have a horrible history in this otherwise intensely parochial annual tournament. From Murray Kidd and Brian Ashton with Ireland in 1996 and 1997 (two wooden spoons) through Graham Henry and Steve Hansen (bottom half of the table in each of their six years with Wales) to Matt Williams and Andy Robinson with Scotland (two sixth places and three fifths), it has rarely brought results.

All Italy's Six Nations coaches have been from abroad. Johnson finished fifth as a caretaker with Wales in 2006 and third last year with Scotland. Gatland is the exception to the rule. In his four Championship seasons with Ireland, his team moved up one place each year to be runners-up in 2001. Then he was sacked. Taking over Wales in 2008, he immediately won a Grand Slam, and again in 2012.

"There are far too many foreign people involved at the top end of the game in our country," the Scottish former Scotland coach Frank Hadden said recently. "There is nothing wrong [with them] individually… but perhaps [there are] not enough who fully appreciate the history and tradition."

Arguably it is paradoxical to have foreigners on the coaching staff when the players must be qualified through birth, ancestry or resi-dency. The BBC television trailers for the Six Nations faithfully intone the elemental nature of the thing: "Rivalry: it's in our blood… our fiercest rivals are those who are closest". The reality is that all four Irish provinces are also in the hands of foreign head coaches – Mark Anscombe (Ulster), Pat Lam (Connacht), Rob Penney (Munster) and Matty O'Connor (Leinster).

As Jackman, the 37-year-old former Ireland hooker who will step up from being an assistant to become Grenoble's head coach next season, explained: "Experience is important, and there just aren't many ways for an Irish ex-player to gain it. I have ambitions in the long term to come home and coach an Irish province, and there are Irish coaches who are doing well in other countries.

''But you have Australians and New Zealanders with experience, and it is inevitable they will get some of the jobs. There's probably a lack of patience in Irish provinces but it's only natural they want someone with a varied CV."

No one can blame Schmidt, a famously diligent and approachable character, for a detached sense of what the world's oldest international rugby championship means to him. "My earliest memory is when Scotland, as massive underdogs, beat England in 1990," said the former Manawatu player and coach with Bay of Plenty, Auckland Blues, Clermont Auvergne and Leinster. "It was great viewing, and ever since then I've had an interest in the Six Nations. Coaching Super Rugby, you'd see if you could magpie a few ideas, steal a few shiny bits."

Jackman said: "It must be strange, a weird emotion for Joe, especially last November when he was coaching against his own team, the All Blacks. But I'd be the same. If Grenoble played Leinster, my allegiance would be with Grenoble."

Ireland are looking to deny Scotland only a second win in Dublin since 1998. Last year the Scots under the effervescent Johnson – who will be succeeded by Vern Cotter, a New Zealander, in the summer – somehow beat Ireland at Murrayfield despite only having 20 per cent of the possession.

Tomorrow they will be boosted by the return after injury of the excellent full-back Stuart Hogg, who missed the autumn Tests.