Manchester suffered a humiliating 3-1 defeat to Brentford at the Gtech Community Stadium on Saturday.
Brazilian forward Igor Thiago was the star of the show, netting twice in the opening 20 minutes.
Thiago broke the deadlock in the 8th minute, timing his run perfectly to beat the offside trap before calmly finishing past Altay Bayindir.
Twelve minutes later, he tapped in a rebound to make it 2-0.
The Red Devils briefly sparked hope in the 26th minute when Benjamin Šeško pulled one back after a scramble in the Brentford box.
The 71st minute was the pivotal moment. After Bryan Mbeumo was fouled, United captain Bruno Fernandes attempted a penalty kick, but Brentford goalkeeper Caoimhín Kelleher made the correct guess and stopped his attempt.
Substitute Mathias Jensen put salt in the wounds well into stoppage time. He broke clear on the break and curled a long-range goal that went over Bayindir to give Brentford a 3-1 victory.
The defeat is a significant lift for Brentford, who can now move forward with confidence.
For Manchester United, Just a week after defeating Chelsea, the club has been thrust back into crisis mode, with Amorim’s future under close examination as the international break approaches.
