LONDON (Reuters) - Pep Guardiola's 100th Premier League game in charge of Manchester City had looked all set within the first half-minute at Newcastle United to be just the latest record-breaking milestone in his triumphant English reign.
Instead, it turned into the mystifying ordeal of a wholly unexpected 2-1 defeat at St James' Park that leaves the brilliant Spanish coach facing the toughest challenge of his City stewardship as he sees their title slipping away.
Sergio Aguero's goal in 24 seconds was quickest in any Premier League match this season but was only the prelude to one of City's most sluggish displays as Newcastle fought back to win with second-half goals from Salomon Rondon and a Matt Ritchie penalty.
It left City still four points behind Liverpool at the top of the table, with Juergen Klopp's pacesetters now having the chance to stretch the lead to an intimidating seven when they host Leicester City on Wednesday.
It left Guardiola sounding just a little resigned as he pondered how his men can possibly claw back that deficit against a Liverpool side that has lost just once in the league this season -- against City at the start of the month.
"We had a chance today to reduce the lead. Tomorrow is a game for our opponent (Liverpool). When you are behind, you have to win games and we couldn't do that," he said.
City have been touted as the potential winners of four trophies this season -- not by Guardiola himself, it should be said -- but this loss made any such talk seem fanciful.
"I know the challenge is big, being in all competitions is what it is," shrugged Guardiola. "If you want to go up as a club, you have to accept that challenge. I prefer to be in that position."
The real shock for him, though, must have come in seeing a side that had stormed their way through January -- Aguero's was their 30th unanswered goal in their New Year rampage -- suddenly look flat and, frankly, quite careless.
"It was not our best night, we didn't make a good performance," he shrugged.
"We didn't take the rhythm of the game, it was slow and we weren't aggressive enough ... The game was not good. We did not defend the second ball well, we have to improve."
For once, City's unremitting pressing and cutting interplay was curiously absent and it meant Guardiola missed out on an outright record of achieving most wins in the Premier League era by any manager in their first 100 games.
It would have been his 74th win -- but instead he will now share that landmark with his old rival, Jose Mourinho, who won 73 of his first 100 with Chelsea while winning the title in successive years.
That's a feat that, for the moment, looks increasingly out of reach for the man who has long since usurped Mourinho as the Premier League's 'Special One'.
(Reporting by Ian Chadband; Editing by Greg Stutchbury)