Every NFL roster has its stars, serviceable veterans and building blocks. In the age of free agency, it's important to stack up on that last category.
What's a building block? We'll focus on young and affordable players with something to prove who fit into three categories.
First, they must have between one and three years of experience in the league. On paper, all first-round rookies seem promising—that's why they're Day 1 picks—so we'll avoid the easy choices. Let's turn our attention to those with pro experience, which provides tangible performances at this level to dissect.