Losing to Arsene Wenger for the first time in 14 games will certainly irk Jose Mourinho but what will trouble him even more is the docile nature of his forwards in the 1-0 loss.
In the absence of Diego Costa who missed the London derby through injury, Loic Remy (who started) and loanee Radamel Falcao (substitute) both had their go in filling the Spanish international's boots.
Costa's boots proved too big fill on this particular occasion but there is every reason to believe it will be running theme throughout the season.
Starting with Falcao, the former Atletico Madrid star was once the world's most feared striker as John Terry and co can attest to when he bagged the first ever European Super Cup hat-trick against them. Without a shadow of a doubt he was on the verge of achieving legendary status in the game, such was his goalscoring prowess.
Two years and an ACL injury later the tables have reversed. Costa is the fans favourite at Stamford Bridge and Falcao is an Old Trafford reject estranged from his parent club AS Monaco.
With a poor Copa America campaign behind him his alarming loss of form shows no sign of letting up. On the other hand, Remy is in relatively sound form but that is worrying for its own separate reasons.
At the age of 28 Remy has scored 83 career league goals. In four seasons (two for Porto, two for Atletico) Falcao, who is 29, netted 93 times.
Whilst Remy remains a good player he has no business being in a title chasing side unless he is third choice. In theory he is third choice but with Costa's hamstring continually proving a thorn in Mourinho's plans and Falcao unable to shake off his descent, Remy will be due more minutes than his talents deserve.
In a transfer window where the likes of Carlos Bacca and Mario Mandzukic were transferred, and others like Alexandre Lacazette and Gonzalo Higuain were potentially available, it is strange Mourinho would handicap himself by taking a risk in Falcao.
Perhaps he should have taken a leaf out of Wenger's book 'bought the league'.