Ruben Amorim insisted he was "not naive" about the "difficult" task awaiting him as Manchester United's new head coach. 

Amorim took charge of his final game as Sporting CP's manager on Sunday, culminating in a 4-2 away win against Braga to maintain their perfect start to the Primeira Liga season.

The 39-year-old ended his glittering career with the Portuguese side having won 164 of his 231 games at the helm (D34 L33), bowing out with a win percentage of 71%, a club record. 

Amorim arrives at Old Trafford after a string of impressive results under interim boss Ruud van Nistelrooy, who went unbeaten across his four games during his temporary stint. 

Though the Portuguese's arrival at the club and the positive results of late have lifted the mood in Manchester, Amorim acknowledged the enormity of the task at hand. 

"I feel ready for the new challenge," Amorim told reporters after his final match at Sporting. "I'm not naive, I know it's going to be very different, very difficult.

"I'm at peace now. I can focus on my new job, and I'm looking forward to starting tomorrow.

"I know it will be difficult to reproduce what I have here anywhere else, but there are other places with different exposure and pressure."

United are yet to confirm the precise nature of Amorim's backroom team and whether Van Nistelrooy will remain at Old Trafford. 

The Dutchman returned to Old Trafford in July as an assistant coach under former boss Erik ten Hag, signing a two-year contract. 

"I have to talk with him [on Monday]," Amorim added. "I will explain everything. I'm very clear, and I will tell you like it is. So let's wait."

Amorim now has 13 days during the international break to prepare for his match in charge, which comes at Portman Road against Ipswich Town on November 24. 

His first Old Trafford outing comes four days later in the Europa League against Norwegian champions Bodo/Glimt.