A back problem has thrown England all-rounder Paul Collingwood's participation in next week's first Test against New Zealand into doubt.
With England due to announce their squad on Sunday morning, one-day captain Collingwood was also set to have an injection designed to help him cope with an ongoing problem with his right shoulder.
England also have a worry over wicketkeeper Tim Ambrose, who was unable to play for his county, Warwickshire, on Friday because of a stiff neck.
An England spokesman admitted it was Collingwood who was giving greatest cause for concern.
"Paul has received treatment for stiffness in his lower back and a sore right shoulder," he said. "He will continue to receive treatment and be reassessed over the next 48 hours."
Collingwood, 31, would be an integral part of any plans to field Andrew Flintoff in a four-man attack in the series opener.
Although Flintoff is deemed fully fit following a fourth ankle operation, England would not want to bowl him into the ground and Collingwood could supplement the attack with half-a-dozen to 10 overs a day.
England are likely to select all-rounder Flintoff for his form with the ball as he bids to play his first Test since the final 2006-07 Ashes defeat.
Flintoff has looked smooth from the off in his latest comeback and his early-season menace was rewarded with seven wickets in the defeat of Collingwood's Durham at Old Trafford on Friday.
The 30-year-old has mustered only 68 runs in seven innings for Lancashire this summer, however, twice falling for nought in his latest outing.
That is not the kind of form to merit a place in the top six and he is being lined up to slot back in at number seven, a position in which he has not been selected since the tour of Sri Lanka in 2003-04.
England's established batsmen have hardly been rich in runs themselves, however, with captain Michael Vaughan's lack of a half-century this season of concern and Collingwood in a real rut.
He has scored just 32 in five innings in all forms of cricket but does have a reputation for pulling performances out of the bag in difficult circumstances.
"It's a bonus if you can come out and score hundred after hundred every innings," he said. "Realistically it's not going to work that way and you come up against difficult conditions.
"Runs would be good to get that confidence going but I'll back myself to go out there and score out in the middle when the time comes.
"I am sure that everybody has got me down as the first one off the team sheet but I am a battler."