Do a Leicester

Verb.
To manage the impossible; to boss it in the face of qualified doubt; to beat insane odds against you.

"England can 'do a Leicester' at this summer's Euros according to Foxes hero Danny Drinkwater" Article Headline in the Mirror (17/05/2016)

Do a Leicester

To achieve something with no expectations as Leicester city football club famously did.

Let's do a Leicester
Overachieve

Doing a Leicester

Making an impossible sporting dream possible.

"It's called: 'Doing a Leicester'," he explained. "And I'm crossing my fingers to 'do a Leicester' at the Olympics."