England have reluctantly had to accept that Kevin Pietersen is feeling too much pain in his knee to be a viable part of their immediate plans.
Pietersen's captain Alastair Cook thought England's most dangerous batsman might be able to defy an injury which first surfaced last month in Queenstown and worsened through the first two Tests against New Zealand.
It was only yesterday it became clear, after scans, that suspected cartilage damage in his right kneecap meant Pietersen could not be considered for the series decider at Eden Park tomorrow.
England will therefore turn once again to Jonny Bairstow as the only specialist batsman in their squad to replace Pietersen.
In the longer term, they must hope that a best-case six-to-eight week recovery period - without surgery - will have their match-winner back in time for the Champions Trophy and Ashes beyond, and maybe even May's return series at home to the Kiwis.
Pietersen, who will also miss the Delhi Daredevils' Indian Premier League campaign, has served England well for much of this winter after the "reintegration" process which followed a period of soured relations with his employers and team-mates last summer.
Cook is widely-credited as a driving force behind efforts to ensure his captaincy tenure, after the retirement of Andrew Strauss, began with Pietersen back in the fold.
Today, he unequivocally endorsed the batsman's commitment to the England cause in a winter which featured a match-winning hundred from him in Mumbai - on the way to a famous series victory.
Cook conceded, however, England were hoping Pietersen would also stay the course in New Zealand.
Stony-faced as he addressed a press conference, delayed by almost an hour today, the captain said: "We did [think he'd be okay].
"He felt he could get through, and we felt he could get through, those two games.
"This game might be a step too far.
"He's not fit to play, so we need a new player in.
"It's important he's fit as soon as he can be. You do look sometimes at future planning, but I think if this was an Ashes Test match he (still) wouldn't be playing in it."
Cook has been highly-encouraged by both Pietersen's demeanour and performances since his months of exile and rancour last August and September.
"Yes, without a doubt ... throughout this winter," he said.
"That innings in Mumbai was a fantastic one at a very crucial time, and that shows his worth to the team.
"Not many people could play that innings, and that's why we need him in an English shirt as often as we can.
"We're getting robbed of him in this game. But it gives Jonny a great opportunity."
Pietersen has failed to hit the heights in two draws against the Kiwis, but did battle his way to a half-century in Wellington most recently.
"He hasn't been 100% fit, but he's put his body on the line trying to play for England," said Cook.
"That's all you want from all your players.
"It's (been) great to have him back. I said at the beginning of the winter, in India, you want to be able to pick from your best squad.
"We managed to do that, and he's fitted in really well. It's just a shame that his winter has ended a little bit early with his knee."
Pietersen's defection is the second through injury on this tour, off-spinner Graeme Swann having had to miss the whole Test series to have surgery on his bowling elbow.
Cook added: "You want your best players available. But injuries - they've happened to Swanny on this tour, and now KP - are part and parcel of international sport.
"He's played through a bit of pain for those first two games.
"At the moment, it's not great for English cricket that one of our senior and best players has an injury concern going into the summer."
Cook remains optimistic, however, that Pietersen will be back for the main events in perhaps the highest-profile year in English cricket history.
"If the injury is not so bad, as we hope, and it's just a bit of rest and no operation needed then on the plus side he gets a bit of time off and is ready to go for the Ashes.
"There are quite a lot of sportsmen who play when they're not 100% fit.
"If you asked Jimmy (Anderson), through certain times in his spells, and Broady [Stuart Broad] when his heel (injury) was coming on, they felt it.
"He did, but felt he could get through the game and produce good enough performances to justify his selection."
Ultimately, England have had to be advised by Pietersen as well as their medical experts.
"The scans can only tell so much. It's got to be how the player feels as well," said Cook.
"My knee might, does, feel different to KP's.
"It's important now we don't jump to too many conclusions. He goes home and gets to see the specialist, and sees exactly what's wrong with him.
"We've just got to have a bit of luck with the scan in a couple of days' time."