Oxford Dictionary

Sandbag:
Deliberately underperform in a race or competition to gain an unfair advantage.
♦ ‘Either they sandbagged during qualifying and practice or they gave very high downforce to the cars to make them slower during those sessions.’

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Webster

US informal : to hide your true abilities or purpose in order to deceive people, gain an advantage, etc.


♦ no obj He claimed he was playing badly because of an injury, but I think he was sandbagging.


♦ + obj I think he was sandbagging us.

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American Slang:شل بازی کردن

tr. to deceive someone; to fool someone about one’s capabilities. • Don’t let them sandbag you into expecting too little. • The guy sandbagged me, and I wasn’t expecting him to shoot the ball.
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Heritage
To downplay or misrepresent one's ability in a game or activity in order to deceive (someone), especially in gambling: sandbagged the pool player by playing poorly in the first game when stakes were low.
ضعیف نشان دادن

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