Great Britain will be without Andy Murray for Friday's opening Davis Cup singles matches against Serbia & Montenegro in Glasgow.
Victory will put Great Britain one win away from the elite World Group
But Murray, who has been suffering all week with a bacterial infection, has been selected alongside Greg Rusedski for Saturday's doubles.
Murray said: "I feel 10 times better than on Sunday and Monday but I felt I couldn't justify playing on Friday."
Rusedski and Arvind Parmar will now play in Friday's singles rubbers.
The first match at 1200 BST will see Rusedski face Janko Tipsarevic, followed by Parmar - yet to win a singles match in the Davis Cup in five attempts - against Novak Djokovic.
"From a totally selfish point of view it's a great opportunity for me to have another go and get back out there," Parmar told the LTA's website.
Rusedski and Murray will face Nenad Zimonjic and Ilia Bozoljac in the doubles at 1300 BST on Saturday.
Murray said the ankle ligaments he injured in Miami last month were no longer a concern.
GB v SERBIA & MONTENEGRO
Rusedski v Tipsarevic
Parmar v Djokovic
Rusedski/Murray v Zimonjic/Bozolijac
"I hit balls for the first time yesterday and felt okay afterwards, and I played for an hour today, but I didn't think it was right for me to play if I was not 100%."
And Murray admitted that he had been advised not to play at all.
"The doctor's advice would be not to play because of what can happen with infections if you come back too quick," said Murray.
"He told me if it was his son, he would say not to play but it was obviously my decision if I wanted to play."
Great Britain captain Jeremy Bates added: "I'm not prepared to put Andy in a position that jeopardises his health.
"He is well on his way to recovering from a serious infection and it's a question of letting that run its course.
"To expect three days out of him is a little much and it's a question of being sensible really.
"He is very keen to play and be involved and everyone wants him to be involved, but you can't risk him playing here and then being out for three months."