Man Utd fans were left scratching their heads after an utterly woeful first half away to Huddersfield on Saturday afternoon.
Unbeaten through the first eight games, and having dispatched of most opposing teams with relative ease, Mourinho's side struggled from the off but when Phil Jones went down with an injury in the 23rd minute, things began to get out of hand for the side placed 2nd in the Premier League table.
Jones has been one of the better performers and a reason for the defensive stability seen thus far, but when his replacement Victor Lindelof was called on to make his second league appearance - after playing one minute away to Liverpool - he had an absolute shocker.
Man Utd fans had expressed their uncertainty with the signing of Lindelof as early as pre-season as he failed to fit in at the speed that other new signings have done, and when he cost Man Utd the second goal after misjudging a routine long-ball, the knives were out.
Don't want to be too cruel but in the ten minutes since Victor Lindelof came on MUFC have conceded as many goals as previous eight PL games
— Daniel Taylor (@DTguardian) October 21, 2017
Lindelof looking like the most un-Mourinho defensive signing since Khalid Boulahrouz. Tuanzebe might feel aggrieved. #mufc
— Samuel Luckhurst (@samuelluckhurst) October 21, 2017
Namanja Vidic turned 36 today and he'd still be more useful than Lindelof. pic.twitter.com/zNNnmbEi81
— ً (@utdstreet) October 21, 2017
Lindelof is shocking man. Genuinely.
— The United Link (@TheUnitedLink) October 21, 2017
Is Lindelof Prunier in disguise??
— United In Focus (@UnitedInFocus) October 21, 2017
Lindelof having a shocker. #MUFC
— Alexis Nunes (@alexisenunes) October 21, 2017
Lindelof costs us the game. Absolutely embarrassing, that’s why he’s not played a single PL game yet.
— Hesham Bilal-Hafiz (@hesham786) October 21, 2017
That is absolutely atrocious defending. Lindelof doesn't look anywhere near ready to play for Utd
— Pilib De Brún (@Malachians) October 21, 2017
Christ Lindelof. That’s shocking.
— Stephen Howson (@MrStephenHowson) October 21, 2017
It has been a very difficult start for the Swede.
Mourinho has come out and said that he needs time to get up to speed, and while he has featured in all of Man Utd's Champions League games thus far he has been held back in terms of the Premier League and the above mistake is exactly why.
It would be silly to write him off as a signing just yet, and while we have seen many players fade out of the picture after struggling initially, Lindelof can look at Marcos Rojo as an example of someone who United fans dreaded seeing in the team to one of their regular starters last season.