The Indianapolis Colts have done quite well at drafting offensive linemen under GM Chris Ballard. From top to bottom, it's only semi-rivaled by linebacker when it comes to his best-drafted position, and even then remains his best hit rate. Ballard had drafted 13 offensive linemen in his nine drafts leading to this recent draft haul, arguably not missing on a single selection considering their draft range. Each of his four offensive linemen drafted in the first three rounds (Nelson, Smith, Raimann, Goncalves) has or is set to become a mainstay starter for the Colts, while the remainder of his draft selections have come on Day 3 (rounds 4-7) of the draft. Establishing continuity across an offensive line typically comes via free agency and/or the top rounds of the draft, yet Ballard has been able to find starters in the later rounds at a strong rate, especially as of late.…