Alston scored the Broncos' first four points in overtime but it was Jessup who gave Boise State (2-2) the lead for good with a 3-pointer. He added a steal and dunk plus two free throws.
Jessup was only 3 of 13 from the floor -- 1 of 9 in regulation -- and his only 3-pointer was just the third for Boise State on 19 attempts. But the Broncos were 19 of 27 at the free-throw line to BYU's 5 of 7.
Boise State's RJ Williams added 18 points on 6-of-6 shooting before fouling out with 1:48 left in regulation, which ended at 58-all after neither team scored in the final 1 1/2 minutes.
Alston, who posted his first career double-double, became the first Bronco ever to score at least 20 points in each of the first four games of a season.
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