"This time, there won't be any surprises.

But there's still uncertainty.

Coach Jim Schwartz announced Wednesday rookie Matthew Stafford will sit and Daunte Culpepper will start at quarterback Sunday at Baltimore.

Yet it remains an open-ended question when Stafford, who aggravated a left shoulder injury in last week's loss at Cincinnati, will return to the field.

Asked if this was just a one-week hiatus for his rookie No. 1 overall pick, Schwartz said, "Probably too early to tell there, but there's a chance that it is, yes."

"It's a situation where if he hadn't taken that hit in the fourth quarter of the Cincy game, we wouldn't be having this discussion," Schwartz said.

But he did, and we are. And even Schwartz acknowledged the Lions "want to avoid the situation where it becomes something chronic" with Stafford's sprained AC joint in his non-throwing shoulder.

"Structurally, everything is still on course there," Schwartz said. "It's a tremendous amount of pain, it's sore and we just wanted to avoid a continuing cycle of come back, get hit, come back, get hit. We'll give it time to rest and put it behind him."

How much rest will he need? Stafford didn't speak to reporters, where he was a bystander during practice, with Culpepper taking the first-team reps ahead of Stanton, as expected. But Stafford made his weekly radio appearance on WJR later in the day.

"I'm sore enough and feeling enough pain that we collectively felt like it was probably a better decision to not play this week," Stafford said. "Structurally, it's not getting any worse, which is good. It's just one of those deals that it's pretty painful and there's some swelling, and all that goes into it. Hopefully, that'll die down with some rest. ...

"I think it's a week-by-week deal. We'll look at it and see how I'm feeling and see how it's progressing at the end of this week and just take it game by game."

Culpepper played the final 3:36 of last week's game after the Bengals' Dhani Jones slammed Stafford to the turf on a fourth-down incompletion.

For Stafford, who'll likely be the emergency third quarterback Sunday, it'll be his third missed start of the season. But it'll be his first since suffering a separated shoulder at the end of the Nov. 22 win over Cleveland. Four days later, Stafford started the Thanksgiving game against Green Bay despite not practicing all week -- a move that caught Culpepper off guard.

Culpepper admitted it'll help "not having any doubts of which way we're going or what's happening." Schwartz said he told the quarterbacks of his decision Monday.

"Clearly, it's better to know," Culpepper said. "The old saying is, "Knowing is half the battle." And when you know the situation, you know how to handle what you're going into. ...

"But the thing is, I get paid to be ready whenever, and I'm ready now." "