London - Pep Guardiola faces one of the biggest challenges of his glittering managerial career as the Manchester City boss tries to stop his side's surprising slump.
As Guardiola paced the touchline during Saturday's chastening 4-2 defeat at Leicester, the exasperated Spaniard's message to his players appeared to fall on deaf ears as the hosts ran rings around his bewildered team.
It was a shocking sight for City fans who had expected Guardiola to bring the swaggering style that won him plaudits and prizes in equal measure during his spells at Barcelona and Bayern Munich.
Less than three months ago it was easy to imagine Guardiola would soon be making room for more medals in his packed trophy cabinet as free-scoring City reeled off 10 successive wins in all competitions.
Yet that blistering start has proved something of a false dawn for Guardiola, whose arrival from Bayern in pre-season for his first experience of English football was heralded as the start of another dominant period for the serial silverware collector.
Having won three Spanish league titles and two Champions League crowns with Barca and then led Bayern to three Bundesliga triumphs, few were willing to bet against Guardiola conquering the Premier League in similar fashion.
Any doubters wondering how the 45-year-old would cope with having to rebuild an ageing and underachieving City squad in a league far stronger from top to bottom than those he dominated in Spain and Germany were widely dismissed by his advocates.
But there are growing signs that Guardiola isn't going to find his City experiment all plain sailing.
The first cracks appeared in a 3-3 draw against a passionate but painfully limited Celtic in the Champions League and those defensive flaws were laid bare by Tottenham a few days later as Guardiola suffered his first City defeat.
Guardiola's response has been unexpectedly flustered.
He has constantly tinkered with his team line-up, making an incredible 46 changes in City's first 14 league games -- 12 more than any other manager in the top flight this season.
All the alterations have left City badly lacking continuity, chemistry and coherence, with the result that they fall apart all too soon once events conspire against them.
Kevin De Bruyne, the brilliant Belgian playmaker, has been used as a central midfielder, attacking midfielder, winger and a striker as Guardiola searches for his best role.
In defence, centre-backs John Stones and Nicolas Otamendi have looked baffled by what Guardiola asks of them and, while that doesn't reflect well on the players, it is also a manager's job to extract maximum performance from the tools at his disposal.
Against Leicester, he went with a three-man defence comprised of Stones and two full-backs in Bacary Sagna and Aleksandar Kolarov.
Unsurprisingly, the makeshift line-up was brutally exposed by the pace and direct running of Leicester striker Jamie Vardy, who feasted on City's confusion to end his goal drought with a hat-trick.
City have kept just two clean sheets in 15 league games, yet Guardiola gave a curious response when asked if his players needed to work on tackling after being beaten to the punch time and again by Leicester.
"It's typical here in England when they talk a lot about the tackles. I'm not a coach for the tackles. So I don't train the tackles. What I want is to try to play good, score goals, arrive more," Guardiola said.
"It's another aspect of football, but we're not going to win or lose because of the tackles."
Guardiola's commitment to his purist principles is commendable, but on the evidence of the last few weeks he must adapt to the unforgiving Premier League quickly to quash a growing crisis of confidence.