The Portuguese renews hostilities with Pep Guardiola in the first derby of the season but his name has already been etched in history.
Following a short new manager bounce after Erik ten Hag's sacking, Amorim has since overseen two successive Premier League defeats.
A 2-0 loss away at Arsenal before a shock 3-2 defeat to Nottingham Forest within a week has left the club in 13th in the table.
This is the lowest position the Red Devils have started a Premier League Manchester derby since August 2007 when they were 16th.
On that occasion, Geovanni's shock first-half strike sealed a 1-0 win for City to continue Sven-Goran Eriksson's perfect start as manager.
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However, that meeting came just three games into the season and Sir Alex Ferguson bounced back to win the title the following May.
Unfortunately for Amorim, their current spot of 13th is the lowest United have started a top-flight Manchester derby that has come at least 10 games into a season since February 1990.
That 1-1 draw carried a lot more weight behind it - having come just weeks after Ferguson had found himself on the brink of the sack.
The legendary Scot was appointed manager at Old Trafford in 1986 but took four years to finally deliver silverware with an FA Cup.
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Man United's then-chairman Martin Edwards has admitted he would have sacked Ferguson had they lost in the third round that January.
Mark Robins famously saved Fergie's job with the winner against Nottingham Forest to set the Red Devils on their way to winning the competition.
A month later United came into a crunch local derby in a lowly 17th spot and avoided a morale-sapping defeat by battling to a 1-1 draw.
Ferguson eventually oversaw their lowest league finish in 13th that May since their relegation from the First Division 15 years prior.
The FA Cup triumph helped ease the growing pressure and ultimately paved the way for a period of Premier League dominance.
Ferguson never finished outside of the top three following the top-flight's rebrand before his retirement in 2013.
His exit subsequently led to their lowest Premier League finish under his immediate successor David Moyes who had the club in seventh.
Ten Hag went one step further last season by finishing a spot lower, with an FA Cup also buying him some more time.
Unlike Ferguson, the Dutchman couldn't use the Wembley success as a stepping stone to further glory and was sacked in October.
Amorim is the man tasked with picking up the pieces but has only managed to rise one position from the 14th which Ten Hag left.
As a result, the record books have already been changed from the first whistle against City but three points will still be up for grabs.
Amorim will also be buoyed by his impressive Champions League win over Guardiola's City with former club Sporting Lisbon last month.
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