NFL, Triple RED!!!
In 10 seasons of NFL study there has only been one time that an NFL TWL game/spread "made it" to "a triple red" (3,5,7). Not including playoff games that is 2560 games so it is even a larger sample. This is very topical since 1) NFL spread markets are currently "the king" in US markets 2) It happened this past year. So just for regular season games, that is .039% which, in statistical terms on a distribution is beyond 3 standard deviations of probability which is 99.6%. That was Dallas vs Pittsburgh. Here is TWL for that game. Steelers won 24-19 (Dallas win ATS).