Ruben Amorim has warned Manchester United fans that masterminding Sporting's stunning Uefa Champions League win over Manchester City on Tuesday is no guarantee he will have immediate success at Old Trafford.
Amorim, 39, last week accepted United's offer to succeed Erik ten Hag as manager and will take charge of the troubled Premier League club on November 11.
Regarded as one of Europe's brightest young managerial minds, Amorim delivered a tantalising glimpse of his acumen as Sporting exposed injury-hit City's defensive weaknesses in Lisbon.
Phil Foden put City ahead in the opening moments at the Jose Alvalade stadium, but the visitors wasted a string of chances to increase their lead and Sporting made them pay.
Viktor Gyokeres equalised before half time and Maximiliano Araujo bagged Sporting's second after the break before Gyokeres' penalty capped their incredible fightback with two penalties.
Amorim, who led Sporting to two Portuguese titles in four years, will take charge of his first United game at Ipswich Town on November 24.
But he is far too astute to claim one victory proves he can revitalise moribund United after the club's worst start to a season since 1986/87.
"What I can tell you is that this doesn't mean anything in particular, don't take anything from this," Amorim told reporters.
"It's misleading, we were very lucky today. We cannot transport one reality to another. Manchester United cannot play the way we play and we will have to adapt."
It was Amorim's final home game in charge of Sporting and he was given a rousing response by the home supporters. At the final whistle, his jubilant players gave him a memorable send-off by tossing him in the air in celebration.
"The feeling with my players, the moment with the fans was very special. So I take this to Premier League," he said.
"When I arrive there it's a different world, a different pressure. I will try to be the same. It will be fun, very fun and I'm ready."
Despite handing Guardiola his heaviest defeat since 2020, Amorim paid his respects to the manager he must outwit over a whole season, rather than one game, if the balance of power in Manchester is to shift back to Old Trafford.
City have won six titles in eight years under Guardiola, while United haven't been crowned champions since 2013.
"He is so much better than me at the moment. But I believe a lot in my newest club," Amorim said.
"We will start from a lower level, maybe I can say that, and we will improve the team, the club. Let's see."