Every team has a weakness - with the possible exception of Bayern Munich - they were quite good, weren't they?
So lets have a look at the top Premier League squads and assess their relative weaknesses. And, like every competent doctor, we'll provide the medicine - in the form of a new signing, of course.
Some clubs may have more than one area requiring urgent reinforcements - ahem, Tottenham. While others have clear and obvious weaknesses in otherwise promising squads - Chelsea, that's you.
Even the Premier League champions need to strengthen. Just look at their Champions League competitors.
Bayern Munich added Mario Gotze and Pep Guardiola before they'd even won the competition, Barcelona have picked up Neymar, Real Madrid today announced the capture of Isco. They're not messing about.
United's transfer business under David Moyes so far amounts to a Chilean under-20 right-back. Work remains outstanding.
They've been linked with all the top names - Edinson Cavani, Robert Lewandowski and even Cristiano Ronaldo. But they would be luxuries considering the presence of Robin Van Persie and Wayne Rooney.
The squad's weakness lies elsewhere - and you can probably guess where. But we'll save the surprise.
Anyway, scroll through the article using the arrows at the top or bottom of the page...