Thursday's announcement that Vaughan would have a fourth operation on his troublesome right knee on Monday, ruling him out for four to six months, has forced the selectors to consider an alternative captain.

Key all-rounder Andrew Flintoff filled in for Vaughan when he was forced out of the tour of India in March and also in the drawn home series against Sri Lanka.

But Flintoff has been forced to sit out the NatWest Series with ankle trouble and is by no means certain of being fit for the opening Test against Pakistan starting at Lord's on July 13.

In his absence Andrew Strauss has led a side decimated by injuries to four successive defeats against Sri Lanka, who are hoping to wrap up a 5-0 series whitewash in the final match at Headingley on Saturday.

The situation has given England a difficult decision and coach Duncan Fletcher said: "From my point of view I just want the best person for the team and we'll be deciding that before the first Test."

Another alternative could be Marcus Trescothick, who has filled in on occasions but has only just re-established himself back in the side after flying back from India with personal problems.

Whoever the selectors consider for this summer, they are not prepared to discuss the captain for the winter tour of the Ashes yet until more information is known about which players will be available.

Vaughan is unlikely to play a part, certainly for the early stages of the tour, while both Ashley Giles (hip) and Simon Jones (knee) have also recently had major operations.

"We won't be making any quick decisions about who is going to captain the side in the winter because at the moment we don't know," explained chairman of selectors David Graveney.

"Until the situation becomes a little clearer later in the summer we won't be looking at that issue. We need to get as much information as possible about the injured players before we consider things."

For the time being, the overwhelming emotion is sympathy towards Vaughan as he begins yet another long process of rehabilitation towards his comeback.

"I have been ringing him every day during this period and he has been battling really hard to recover from this injury, working long hours on his own in the gym so we all feel for him," added Graveney.

"He is a human being so he's bound to have got down during this period. He is desperate to play for England and has been hearing how England can't play without Michael Vaughan so you can just imagine how that has made him feel."