Manchester City are sweating on the extent of a "stupid" injury that threatens to rule Sergio Aguero out of a key stage of the title run-in.
When Aguero missed last weekend's draw at Stoke, Blues assistant-boss David Platt dismissed it as a minor ankle injury the club's £38million record signing had suffered in training the day before.
Now manager Roberto Mancini has revealed the problem to be more serious, and certainly more complicated.
Mancini was cryptic in his explanation, leaving the significant fact about exactly what has happened to Aguero unanswered.
However, he did confirm the South American would miss today's encounter with Sunderland at the Etihad Stadium and could not say for certain whether Aguero will have recovered by the time City head to Arsenal on April 8.
"Sergio has a problem in his foot but it is better we don't talk about it because it is a stupid injury," said Mancini. "It is not his fault but he can't play with this injury for a week, 10 days, two weeks? I don't know.
"For us it is a big problem because we lost Sergio against Stoke and tomorrow he can't play. We hope we can recover him for Arsenal but I don't know if it is possible. I am really disappointed and I hope it won't be weeks."
Mancini declined to elaborate but even the bare details raise significant questions as he had already stated that Carlos Tevez was not fit enough to be handed a starting spot against a Sunderland side that have already beaten City once this season.
That leaves Edin Dzeko, who has scored just five times in his last 25 appearances and none in his last six, and the enigmatic Mario Balotelli as Mancini's only other forward options.
Mancini is clearly prepared to engage in a mind-games war with Ferguson if required, insisting it is just as big a part of the Italian game as it is on these shores.
United's run of nine wins and a draw from 10 of the toughest matches has led many to conclude that City's championship hopes are about to be dashed.
Some United fans have already had T-shirts printed crowing at a record 20th title.
Mancini is ignoring that bait. And he believes his players should too.
"Our motivation should only be to take this championship," he said.
"The other situations, outside the pitch, with supporters or what other people say, are not important. It is clear that they have done very well for the last eight weeks but in eight games, anything can happen.
"Everything is in our hands. If we win all the games and win the derby, we can win."