The dirty tricks that got Sunderland to the playoff final

But that's not all. According to reports, on a hot day in Sunderland, the remote‑controlled heating in the away dressing room had been turned up to the maximum temperature.

If the first example feels like an astute (and perfectly legal) maneuver from Sunderland's French manager Regis Le Bris, the second feels like pure shithousery.

It's not the first time managers have crossed the line. In 2019 Leeds charismatic manager Marcelo Bielsa admitted that he sent members of his coaching staff to spy on their opponents training sessions. Cheating or just good preparation? Said Bielsa at the time:

"Many condemning the behavior, saying that it was not ethical, it was not moral. I observed all rivals we played against. We watched all the training sessions before we played them. What I have done is not illegal. We can discuss it, it's not seen as a good thing, but it's not a violation of the law.

Leeds United were investigated, fined £200,000 and given a severe reprimand.

Examples of questionable behavior go back much further. In 1987 Rangers manager Graeme Souness shortened their pitch to restrict the expansive play of Dynamo Kyiv, while in 2000 Wales' Mark Hughes shaved some yards off the touchline to counter Brazil's explosive wingers.

It's rare for these kind of tactics to happen so visibly at a managerial level but as every soccer fan knows, practicing "dark arts" happens all the time - from deliberately trying to injure an opponent, diving to win a penalty, blatant time-wasting and so on. Especially from teams managed by Jose Mourinho.

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