But because Schwartz threw the challenge flag on a play that would have been otherwise reviewed automatically, he received an unsportsmanlike penalty. The result was that the play was not reviewed by rule, and Forsett's TD stood. That gave DET a touchback up by 3, giving HOU a 0.35 WP.
That's a cost of 0.17 WP. It essentially doubled HOU's chances of winning at that point.