Wales' Warren Gatland questions Dylan Hartley's value
Northampton's Hartley and Blues' Williams clashed during the Heineken Cup
Wales coach Warren Gatland has picked out England hooker Dylan Hartley as a weak link ahead of their Six Nations match in Cardiff on 4 February.
Hartley is expected to pack down between Andrew Sheridan and Dan Cole.
"England imploded a little bit against South Africa, and... I saw Hartley go to pieces [for Northampton] against Leicester," Gatland said.
"He's always got a lot to say, hasn't he? Let's see what he has got to offer and how he fronts up against us."
Hartley has not endeared himself to the Wales camp this season after two explosive Heineken Cup clashes between Saints and Cardiff Blues, both won by the English side.
A flare-up between the Northampton hooker and opposite number Gareth Williams ended with both being sin-binned in the Pool One encounter at Franklin's Gardens.
Then Blues' Wales scrum-half Richie Rees received a 12-week ban after being cited for making contact with the eye area of Hartley during the return fixture a week later.
Gatland fully expects England to come at Wales through their pack, which is hardly a surprise given that Wales will be without their injured British and Irish Lions Test props Gethin Jenkins and Adam Jones.
"England have no choice but to take us on up front," Gatland said.
Gatland considers World Cup selection
"Their front row is not particularly mobile and they are limited without [injured forwards] Courtney Lawes and Tom Croft. The strength of their team will be scrum-time, a driving lineout and physicality.
"England played some great rugby against Australia in the autumn, but I think they then got a little bit of a surprise against South Africa because they were very physical against England up front.
"The last few years we've had a great record against England, nothing to fear, and we should be favourites at home."
Jenkins is likely to miss the entire Six Nations after surgery on his toe injury, but fellow prop Jones could return from his elbow problem within six weeks.
Gatland says that there could also be a place waiting in his squad for young Scarlets wing George North and new Saracens recruit Gavin Henson once they overcome their injuries.
North made an impressive try-scoring international debut against South Africa in the autumn, while Henson is finding his feet again in professional rugby after taking a 20-month sabbatical from the game.
"There's still one or two players who may be added to the squad later on," Gatland added.
"You've got someone like George North who is coming back from injury; Gav [Henson] we've stated needs to play some rugby and get some games under his belt.
"I thought when he came on for Saracens against Leinster [in the Heineken Cup] before he pulled his calf, he showed a couple of nice touches.
"It would have been nice to see him play that game, get one or two more games under his belt and he may have come into contention.
"But until he does that we won't be looking at Gavin, he just needs to play some more rugby."
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