Crossword Genius

Obstructed by footwear? (7,2)

Ross

I believe the answer is:

clogged up

I'm a little stuck... Click here to teach me more about this clue!

'obstructed' is the definition.
(clogging up is a kind of obstructing)

'footwear?' is the wordplay.
I cannot quite understand how this works, but
'footwear?' could be 'clog' (clog is a kind of footwear) and 'clog' is located in the answer.
This explanation may well be incorrect...

'by' acts as a link.

Can you help me to learn more?

I've seen this clue in The Daily Express.
Want a hint initially instead of a full solution? Install my app