The Broncos last spring entered the middle rounds of the NFL draft on the hunt for game-breaking talent. And when Carlos Henderson (third-round pick) and Isaiah McKenzie (fifth) started making plays under the glaring August sun at training camp, it appeared Denver would have a youthful injection to its sagging offense in 2017. As the Broncos prepare for the 2018 combine in Indianapolis next week, they still don’t know whether the two speedy wide receivers they selected in last year’s draft are destined to make an impact.