Leicester City v Manchester City: Going is getting tough for the Foxes
There is only one question clubs in Leicester City's position are ever asked. When will your bubble burst?
It is put with a kind of glee, as if the Premier League can only be taken seriously when it returns to its "big four" normality, and when the final whistle went at Anfield on Boxing Day, perhaps those inquisitors could hear the gas escaping from the balloon.
Neither Jamie Vardy nor Riyad Mahrez, the two men most responsible for propelling the club to the summit of the Premier League, finished the 1-0 defeat at Liverpool. Vardy was unwell and Mahrez was exhausted.
The greatest enemies Leicester will face in the title run-in is weariness and nerves. Their manager, Claudio Ranieri, said they should "clear our minds and restart" before facing Manchester City tonight, adding they had been "nervous and anxious" on Boxing Day. "It is important that we recover our energy and show our football," said the Italian.
Tonight, Leicester may be without not just Vardy, who is suffering from what Ranieri called "a fever", but men like Jeffrey Schlupp and Danny Drinkwater, who have gathered fewer headlines this season but whose contribution has been a solid one.
Every fairytale has a twist and it would be wishful thinking that Leicester would not suffer a blip.
No team since Nottingham Forest in 1978 have won a title so unexpectedly and Brian Clough's freshly promoted side faltered badly in November and faced their nearest challengers, Everton and Liverpool, over Christmas time.
They drew against both and ended the period five points clear of Everton and six of Liverpool in the years when a win bought just two points.
The other template Ranieri might examine is Norwich, who were eight points clear at the top of the Premier League at the start of December 1992 and then failed to score in any of their next five games. Manchester United finished as champions and Norwich ended up third.
Leicester have never had the luxury of those kinds of cushions but they can reassure themselves that every side bar one - Aston Villa - who led the Premier League on Christmas Day finished in what would now be a Champions League qualifying position.
Should Leicester achieve that, it would still make them team of the season in many people's minds.
Manchester City were prepared to take few chances with this fixture. Manuel Pellegrini had planned to start with both Vincent Kompany and Sergio Aguero.
But Kompany's withdrawal after just eight minutes of his comeback against Sunderland on Boxing Day means City will have to entrust their central defence to Nicolas Otamendi and Eliaquim Mangala, a combination that has seldom inspired confidence.
Bacary Sagna, who will start at right-back at the King Power Stadium, said Leicester's transformation from Championship to Champions League material did not come as a big surprise.
"They have quality players and you could see that last season," he said. "They play as a team and they fight as a team and they are very dangerous. I heard about Mahrez in France when he played for Le Havre.
"Even then, he showed he had the ability to play for a top team. He enjoys his football and is a very instinctive player."
Generally, City have not coped well with the big fixtures this season. Their effortless 3-0 demolition of Chelsea looks less impressive now than it did in August and since then Pellegrini's men have been beaten by Tottenham, Liverpool and Arsenal.
Sagna is sympathetic to the pressures faced by Mangala, who has yet to prove to anyone why he was thought worthy of a £42m fee.
"It is never easy to take criticism, but he is still young," said Sagna, who was the same age - 24 - as Mangala when he joined Arsenal from Auxerre.
"When times get hard, the first ones to be blamed are defenders. We have to deal with it and he is doing his maximum to improve."