Ralph Hasenhuttl says Southampton will have to produce a "perfect performance" if they are to pile more misery on Manchester City.
Premier League champions City have suffered successive defeats to drop seven points behind leaders Liverpool ahead of Sunday's trip to St Mary's.
Saints manager Hasenhuttl believes those losses – to Crystal Palace and Leicester – could make Pep Guardiola's side more dangerous.
"It can be (a bad time to play them) because it's not normal for Manchester City to lose two times in a row," said the former Red Bull Leipzig coach.
"They have also a few injury problems but so much quality in this squad, maybe missing a little bit of self confidence after being in the lead and losing two times.
"It doesn't happen only to Southampton but also Manchester City can lose after getting the lead.
"We expect the most difficult challenge that is possible.
"If we want to keep something in St Mary's we have to play a perfect performance."
The Austrian has twice come up against Guardiola in the dugout when the pair managed in Germany.
His Ingolstadt side were beaten on both occasions by Bayern Munich during the 2015-16 Bundesliga season.
Hasenhuttl has plenty of admiration for his counterpart but feels they have contrasting styles of play.
"I have a lot of respect for Pep. He is a fantastic human, a fantastic guy and a hard worker," he said.
"He has a very clear philosophy, I think he makes every player a better player.
"We maybe have a different style, he is all about ball possession and my philosophy against the ball is more important.
"I like his enthusiasm and his clear mind in what he wants to play and there are not many managers with these points-per-match statistics in their life."
Saints go into the game on the back of a defeat after their two-game winning run was ended by Thursday's home loss to West Ham.
Following morale-boosting wins over Arsenal and fellow strugglers Huddersfield, Hasenhuttl believes the Hammers setback provided a reality check.
"We have to be patient about what we expect from this team," he said.
"Nobody could think about winning against Arsenal or Huddersfield. But if people expect now that we put every opponent in the pocket and games (will be) easy for us? No.
"I said it would be a hard and long journey to stay in the league. It is a normal development, with a step back and then we can maybe (take) a step forward."
Mario Lemina is doubtful for the City game with a stomach problem but fellow midfielder Pierre-Emile Hojbjerg returns from a one-match ban.
Young striker Michael Obafemi (hamstring) and left-back Ryan Bertrand (back) remain sidelined.
