VIDEO: Lukaku KO's unsuspecting Chelsea teammate

Thibaut Courtois felt the full force of a Romelu Lukaku shot in training for Belgium.

Thibaut Courtois has not had the pleasure of facing Romelu Lukaku for club or country, testing himself against him only in training for his national side.

He may pay more attention to his fellow Chelsea loanee in the future however, after being knocked to the floor after a powerful strike from his teammate.

Lukaku showed his quality in a training drill with Belgium, and to be fair to him he may have expected Simon Mignolet to prevent the ball even coming as far as him.

The video above should show that it should be a case of lesson learned, just as Jose Mourinho did last season, never underestimate Romelu Lukaku.

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