England still have concerns over the fitness of centre Billy Twelvetrees for Saturday’s first Test against the All Blacks but have been reassured that Owen Farrell and Billy Vunipola will be fine when they arrive in New Zealand to join up with the rest of the tour party.

Farrell and Vunipola needed treatment for cramp in the wake of Saturday’s gruelling Premiership final but are due to fly out as scheduled on Monday along with the other Saracens and Northampton players selected for the tour. Stuart Lancaster will not consider them for the first Test in Auckland but the head coach is confident both players, along with fit-again Dylan Hartley, will be available for the second Test in Dunedin on Saturday week. “Dylan seemed to come through [the final] fine and he’ll definitely be on the plane as he’s an experienced player for us,” Lancaster said.

Lancaster, though, admitted time was running out for Twelvetrees, who has been struggling with a strained ankle. “He still hasn’t trained fully so we’ll see how he progresses during the course of the week but the clock is ticking now,” said Lancaster. “He’s the major one, everyone else should be good to go.”

If Twelvetrees fails to recover in time England will either have to play Bath’s Kyle Eastmond at 12 or shift Manu Tuilagi inside. Despite the late arrival of several regular starters, though, Lancaster insists his side will give the All Blacks a real contest, with the Bath hooker Rob Webber available for first Test selection. “We’re confident in the players we have and the side we can put out,” stressed the head coach.

“A lot of our players have played New Zealand twice and will be looking forward to the challenge on Saturday. This tour will benefit us in the long run because it means a wider group of players will get to play at this level. We want to take every chance we get to play against the best. I believe the side we’ll put out will be competitive. We will be bolstered by the arrival this week of some very good players from the final. We’ll manage them careful and then selection for the second and third Tests will be a challenge.”

Among those in line for a belated tour call-up is Saturday’s try-scoring match-winner Alex Waller but Lancaster insists those flying in will not be guaranteed selection should their first Test replacement perform well. “If someone plays exceptionally well in the first Test but someone else is available for the second Test who played exceptionally well in the Six Nations, that will be a difficult decision.”

New Zealand, meanwhile, have named an experienced 31-strong squad containing 1,125 caps for the three Test series against England. The only newcomers are Highlanders centre Malakai Fekitoa and the Blues lock Patrick Tuipulotu. Their head coach, Steve Hansen, says he is not taking England lightly.

“England have been the most improved side in world rugby in the last two years. Their coach Stuart Lancaster has built depth in his side and a strong culture, so they will be a formidable opponent.”

Ireland’s forwards coach John Plumtree is to step aside for family reasons following this month’s tour to Argentina and will be returning to his native New Zealand. Keith Earls and Martin Moore have withdrawn from the Irish tour squad and will be replaced by Connacht’s Rodney Ah You and Leinster’s Noel Reid respectively.

New Zealand squad: Forwards: Dane Coles (Hurricanes), Keven Mealamu (Blues), Wyatt Crockett (Crusaders), Charlie Faumuina (Blues), Ben Franks (Hurricanes), Owen Franks (Crusaders), Tony Woodcock (Blues), Dominic Bird (Crusaders), Brodie Retallick (Chiefs), Patrick Tuipulotu (Blues), Sam Whitelock (Crusaders), Sam Cane (Chiefs), Jerome Kaino (Blues), Richie McCaw (Crusaders, capt), Liam Messam (Chiefs), Kieran Read (Crusaders), Victor Vito (Hurricanes).

Backs: Tawera Kerr-Barlow (Chiefs), TJ Perenara (Hurricanes), Aaron Smith (Highlanders), Beauden Barrett (Hurricanes), Aaron Cruden (Chiefs), Colin Slade (Crusaders), Ryan Crotty (Crusaders), Malakai Fekitoa (Highlanders), Ma’a Nonu (Blues), Conrad Smith (Hurricanes), Israel Dagg (Crusaders), Cory Jane (Hurricanes), Julian Savea (Hurricanes), Ben Smith (Highlanders).