At his press conference Tuesday afternoon, Tomlin admitted Rainey will be the team's punt and kick return man when the Steelers take on the Broncos in Week 1, but noted he doesn't trust him. He elaborated further by pointing out there are several veterans who could also return kicks, indicating the wrong move or shoddy preparation this week could cost Rainey his spot.
Apparently Tomlin doesn't want Rainey getting too big of a head after two outstanding returns (both nullified by penalties) in the Steelers final preseason game. Or that's one theory, anyway.
The less subtle message to the entire special teams group can be found in the combination of his statement today about Rainey, and the release of every other rookie returner the Steelers brought to camp this preseason. Rainey was clearly the most competent, but outside of the Carolina game, none stood out in any meaningful way. It should be noted WR Antonio Brown (punts) and Emmanuel Sanders (kicks) stand behind Rainey on the return depth chart, and it wouldn't be ideal to have either of them in the return game, given the likelihood of the Steelers carrying just four receivers with them to Denver.