United meet Ipswich this weekend to mark the new manager's first game in charge.
Carragher wrote for the Telegraph: "I cannot wait to see United take on Ipswich Town on Sunday afternoon because we are about to witness one of the most radical mid-season changes in formation and strategy ever imposed by one of the elite clubs.
"Facing the side fourth from bottom might seem a gentle introduction to English football for Amorim. My suspicion is it will be much trickier than many think.United are not just playing Ipswich at Portman Road.
"They face a manager who arguably knows more about the strengths and weaknesses within United’s squad than the new coach."
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