If you've not, it's from a celebrated documentary called Orient: Club For A Fiver, which follows Leyton Orient football club through part of their disastrous 1994/5 season (not quite as bad as last season, mind).
The unfortunate John Sitton was manager for the period covered by the show, of which the clip above is the best-known passage: having difficulty coping with the impossible task he had been given, Sitton (and it wasn't the only time) loses it with his players and offers a couple of them out, two against one. However, also of interest for our present purposes is the moment near the start of the clip when, unusually for a half-time team talk, Sitton takes the opportunity to sack the experienced Terry Howard, right there and then.
The documentary effectively finished Sitton's short-lived career, the bloke having made a public fool of himself. Over the two decades since, a certain amount of sympathy for his fate has developed - you can for instance read a defence of him (with which I don't necessarily agree) here - not because he's perceived as having behaved properly, but because few people who know football think he was particularly bad by the general standard of football managers.
Anyway, that's neither here nor there. To get to the point, the reason the Sitton speech suddenly occurred to me last Monday was that I was so unimpressed by Luke McShane's abject performance against Ference Berkes, I wanted John Sitton to pop up midway through the game and sack him on the spot.