Both chins are suspect, so I need to see what their chins are before I could judge. but there isn't much size separationg the two, Crawford was 156+ somethign against Postol and Errol was 156+ in his last fight and crawford is 5'9 and Errol is 5'9 1/2. So Size isn't so big of a disparity.
Crawford has more speed in his hands and one of the best jabs on the business. SO if he clips spence it would be at the point where Spence is trying to close in the distance and catch him on the way in or counters him while spence was trying to work the body.
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