Stuart Lancaster hasn't given up hope of Dylan Hartley being fit to tour New Zealand - but the England head coach has contingency plans in place if he is not.
Hartley has not played since picking up a shoulder injury against Leicester in March and Lancaster has already named four hookers in a 30-man squad - Luke Cowan-Dickie, Dave Ward, Rob Webber and Joe Gray.
Only Webber has previously been capped however and with Tom Youngs and David Paice also unavailable, Lancaster is hopeful Hartley, who made his 55th appearance for England during the RBS 6 Nations, proves his fitness in this weekend's Premiership final.
"We've named four [hookers] but we have not ruled Dylan Hartley out yet," said Lancaster.
"Dylan's I'm sure going to try and fight his way into the Northampton team this weekend, though I'm not sure how that will play out.
"We want to give him the flexibility and opportunity to come on tour should he play well on Saturday.
"But to cover our bases and if that wasn't to transpire then we have to cover our bases and make sure we have enough for the trip. Losing Tom Youngs and David Paice does bring opportunities.
"Luke Cowan-Dickie is an example, he's been exceptional in training.
"For those who have seen him develop from an international loose-head at age grade into a starting hooker in the Premiership and what he's done at the Exeter Chiefs, he's an example of, for me, the benefits of the tour and understanding who has the ability at the highest level as we look to get more depth in those positions."
Wales' acting head coach Rob Howley has given Sam Davies and Rory Thornton a boost ahead of the RBS 6 Nations by naming the uncapped Ospreys duo in his largely experienced squad for the Autumn Internationals.