One of the byelaws prohibits "people climbing on any wall, fence, tree, barrier, railing or structure without a reasonable excuse".

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The ball caromed back onto the field off the bottom of a black retaining wall just above the fence and was initially ruled in play.

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Previous accidents in which drivers hit crossover gates were severe, but the gates were in the wall and not the fence for Mike Harmon's accident at Bristol in 2002 and Michael Waltrip's at the same track in 1990.

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