Pools were beaten 3-0 at home by previous basement side Carlisle United and the 47-year-old stepped down within an hour of the defeat.
The Cumbrians ran Pools ragged in the second half scoring three times through Steven Rigg, Stephen Elliott and Mark Beck.
Angry home supporters showed their feelings against the manager and the club’s owners with Cooper deciding his time was up.
Cooper leaves Pools with a record of 16 wins, 13 draws and 28 defeats from 57 league games.
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