Martin Truex Jr. was not happy with the way Regan Smith was racing him as Smith tried to avoid going another lap down in Sunday's Folds of Honor QuikTrip 500 at Atlanta Motor Speedway.
Smith, who was running at the tail end of the field after starting the race in 30th, cut in front of Truex instead of allowing the faster car to go by, breaking an unwritten NASCAR rule.
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Truex, who was in seventh at the time, let Smith know his displeasure with the universal signal for any road-rage incident — his middle finger.