Everett, who won the US trials last month in 43.81sec, the second fastest time in history, revealed he was carrying an injury to his right Achilles tendon. 'There is the possibility that I might have to make a decision which will affect the team,' he said. 'As of now, the tendon doesn't feel good, and I wouldn't want to go out if I'm not 100 per cent. I hope for the best, but I'm prepared for the worst.'
If the Olympic silver medallist from Seoul does drop out - and he must make a decision by 10am tomorrow, 48 hours before his first race starts - the rules do not allow for any reserve to be drafted in. All teams here were finalised at the stroke of midnight on 21 July.
Thus, there would only be two Americans - the Olympic champion, Steve Lewis, and Quincy Watts, the 19-year-old who was second in the trials - for Black to worry about. And although the British runner's best time of the year, 48.84, is over a second slower than Everett's, no other athlete outside the United States has run as fast.
Everett's absence from the relay squad would increase the likelihood of there being a place for Michael Johnson, who did not run the 400m in the US trials and who will concentrate here on the 200m. As Johnson has a time of 43.98 to his credit this year, that would appear to be bad news for the British quartet. But the inclusion of the world 200m champion would make waves within the team.
Lewis and Everett have voiced strong objections to the alteration of the US relay selection policy, which has opened the way for Johnson to be picked.
Everett took up the cudgels again yesterday, saying he had lost all respect for Mel Rosen, the US coach. He accused him of having a conflict of interests in his position as a consultant for Nike, the sports company who sponsor Johnson.
Following a recent practice, the US team are believed to have settled on a running order of Everett, Watts, Johnson and Lewis. Andrew Valmon, fourth in the trials, would probably come straight in if Everett was forced to drop out.
Johnson believes he is capable of breaking the oldest world track record, the 200m held by Italy's Pietro Mennea, at the Games. 'I know the track and it's very fast. I wouldn't rule out getting close to the world record,' Johnson said. 'I'm on form. I've come really wanting to be champion'
Meanwhile, Carl Lewis has indicated that the Barcelona Games might see both himself and the world champion, Mike Powell, break the 30-foot barrier in the long jump. 'Mike has already said he feels he has the ability to do it,' Lewis said, 'and I feel I can jump a foot further than I did at the Tokyo world championships. So yes, the possibility is there.'