Referee knocked unconscious...in a friendly (Video)

Many a sportsman's autobiography has described going into the 'zone' when crossing the white line on to the field of play.

When players get into the 'zone' they become a completely different person to their normal character; capable of doing things they would not do in real life. For better or for worse.

It would appear Benfica's Luisao is one of those players who, even in a friendly, is in the kind of 'zone' which can probably be best described frightening.

The angle is a bit dodgy but he would appear to deck the referee in this friendly match with Fortuna Dusseldorf with a solid left hook.

Unsurprisingly, the match was subsequently abandoned.

Take note Paulo Di Canio.

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