MARTIN Johnson has waded into the furore over Dylan Hartley and branded Warren Gatland's attempts to wind up the England hooker as the actions of a man under pressure.

Wales coach Gatland lit the blue touch-paper ahead of a potentially explosive Six Nations showdown in Cardiff next Friday by branding Hartley a choker and questioning his temperament on the biggest stage.

Johnson is not easily goaded into a pre-match war of words but the England team manager, speaking at the championship launch in London, returned fire with force.

Gatland signed a new four-year contract with the Welsh Rugby Union in October but Wales head into the Six Nations without a victory in their last seven Tests.

And Johnson said: "It's about pressure and how people react to it. Where Wales are, they are under pressure as a team with their performances and not winning a game for a while.

"Warren's had a blast. He has said a lot of things. It is not particularly subtle. It's pretty obvious what he is trying to do. Dylan will take it in his stride.

"We rally around guys when they've been singled out. You are potentially giving ammunition to the opposition. It brings the team together.

"With the opening game in Cardiff, they will be desperate to win. So are we."

Gatland, typically, dismissed Johnson's suggestion that he was feeling the heat with a jibe, which referred to the Six Nations target set for England by new Rugby Football Union chief executive John Steele.

"Coaches are always under pressure in this game. At least my chief executive has not come out and said that I have to finish first or second," Gatland said.

"There is always a bit of spice between England and Wales and we will see how (Hartley) responds.’’ Gatland is clearly trying to provoke a reaction from Hartley, the combative Northampton captain who has been known to sail close to the disciplinary wind.

Last November, New Zealand were furious when Hartley escaped any sanction for a forearm challenge on Richie McCaw.

Hartley was sin-binned during the Saints' Heineken Cup encounter with Cardiff Blues last month for fighting with his opposite number Gareth Williams.

The return game at Cardiff City Stadium was just as heated and Wales scrum-half Richie Rees was later suspended for 12 weeks after being found guilty of making contact with Hartley's eye area.

But Johnson is not concerned by Hartley's temperament.

"Dylan has been playing fantastically. He has matured incredibly. He has just led his team through an unbeaten European pool stage and a lot of provocation down in Cardiff and done his talking on the field," Johnson said.

"He doesn't have anything to prove to Warren Gatland. We are very happy with the way he is playing and the way he handles himself.

"We want Dylan to play aggressively. That is why he is in the team.”