The first half on Monday was the poorest of Carrick’s tenure, much worse than in the 2-1 defeat at Newcastle last month when a rusty United were also way below their best and looked undercooked after so little football this season.
United remain in a very strong position to qualify for the Champions League but defensive problems have come at a bad time and the loss of Kobbie Mainoo in the 72 hours before the Leeds match was also a blow.
What followed, with Manuel Ugarte struggling alongside Casemiro, highlighted why revamping central midfield is the priority in this summer’s transfer window. Carrick will be desperate to have Mainoo back for Chelsea.
Losing Lisandro Martínez for three matches for violent conduct for pulling Dominic Calvert-Lewin’s ponytail will be even more keenly felt should Harry Maguire end up being given with a new suspension and miss the Chelsea match.
The England defender was suspended against Leeds after his red card at Bournemouth but faces the threat of an additional one-match ban from the Football Association for mouthing something at fourth official Matt Donohue at the Vitality Stadium following his dismissal.
Telegraph Sport revealed on Tuesday that United will appeal Martínez’s red card. Yet unless the club are successful on that front Carrick could yet be without his three first-choice centre-backs at Stamford Bridge since Matthijs de Ligt is still sidelined with a back complaint that has kept him out since November.
That would mean the manager would be likely to pair youngsters Leny Yoro and Ayden Heaven in the heart of the defence.
Diogo Dalot and Bryan Mbeumo are expected to come back into the starting XI but the latter has struggled for form, as has Amad Diallo, since they returned from the Africa Cup of Nations in January. Matheus Cunha, similarly, needs to show greater consistency.
Carrick faced criticism in some quarters for not changing things sooner against Leeds but it is also worth remembering he was being praised for his positive and proactive substitutions not too long ago.
United are still in the box seat when it comes to the race for Champions League qualification outside the top two but they must emerge from this sticky spell.