Texas safety Kenny Vaccaro is the highest-ranked player at his position heading into the draft. He had 92 tackles (4.5 for a loss), five passes defensed, two interceptions and two forced fumbles in 2012.
Though the Steelers still have both free safety Ryan Clark and strong safety Troy Polamalu safely on their roster, both are on the wrong side of 30 years old. At some point, the Steelers will need to find a workable replacement for one or either of the two, and Vaccaro would be a great jumping-off point.
While he'd be a better free safety, he can also play strong safety, which would give the Steelers some injury insurance at the very least in 2013 and a starter, should either be released or move on, in 2014.
Vaccaro can be a major special-teams contributor in his rookie season—a must for any defensive back drafted by the Steelers, regardless of round. Should Clark or Polamalu hang up his cleats or be released in 2014, the Steelers have a starter available in Vaccaro.
If he's still there at 17, he could very well be best player available, and the Steelers won't really want to pass that up. He can play free or strong safety—he's great against the run as well as in coverage.
Other, more immediate needs may see the Steelers take a pass on Vaccaro if he's still on the board. In a sense, safety is a luxury pick in the first round with both Clark and Polamalu still around, even if there are injury and age concerns associated with the two veterans.
Even if Vaccaro is among the players the Steelers are giving heavy consideration to in the first round, the St. Louis Rams pick at 16, right before Pittsburgh, and they need a safety badly.