Coaches get nervous about starting rookies, mostly because of lack of experience. That's the issue, laid down on the table. It's not easy to be well-prepared for an NFL game. Along with the magnitude of the situation and focusing on a massively complex game plan and your opponents' strengths and weaknesses, rookies also are subject to the high expectations of the fan base and the franchise.
Because of those things, teams often like to err on the side of caution by holding them out until they've shown they can handle the preparation necessary to contribute positively on game day.
For one reason or another, the Steelers will activate two rookies who have yet to play an NFL game - wide receiver Martavis Bryant and defensive lineman Dan McCullers - when they take on the Houston Texans on Monday Night Football. Stephon Tuitt and Dri Archer have already played enough to provide something of an idea of what they can do on game day (Tuitt will make his first start vs. Houston).
Perhaps a less-than-desired level of consistency, leading to a 3-3 mark after six games, has raised the temperature around the entire team and is responsible for the rookies replacing players at certain positions on the team. That might be the case for Bryant, at least, as he's likely to see action inside the red zone, an area that's basically been a no-fly zone for the Steelers during the last few weeks. They're among the NFL's worst teams in red-zone production.
It would seem Bryant is on target to take just a handful of snaps, likely in shorter-yardage situations, where his size can be an asset. A conservative prediction is probably best here; maybe seven or eight snaps.
Tuitt starts at defensive end over veteran Brett Keisel, while former starter Cam Thomas moves inside to take injured Steve McLendon's nose tackle position. The defensive line is thin depth-wise and, with McCullers being the only backup at nose tackle, look for Keisel to split snaps with Tuitt in shorter-yardage situations, but on passing downs, it'll be all Tuitt. Expect him to take a career-high number of snaps, probably somewhere around 30.
McCullers isn't likely to see much playing time at all, but he'll be in on special teams, mainly field goal and extra point blocks. He has a good opportunity to show what he can do, since the struggling Cam Thomas isn't likely to remain a starter for very long if someone is pushing him. Throwing McCullers into the fire probably isn't the best idea (Steelers fans saw last year what can happen when an underprepared, sixth-round pick gets on the field before he's ready), but he can step up to steal a few snaps here and there based on his production Monday.