Harris dislocated two toes in a game at Baltimore on Nov. 1 and missed the second half of that game, as well as the next three -- all Denver losses.
McDaniels said the quick hook on the left-handed Simms had nothing to do with Polumbus' performance, and he said Polumbus remains the starter until Harris gets back.
"He will not play this week. He's doing better. He's getting close. He's worked extremely hard to get back on the field. But I don't think we need to keep that a secret anymore," McDaniels said. "He did a good job yesterday at the workout and it's just not quite ready to go.
"And I don't think this is the week, you're bringing a player off of a fairly significant injury at his position, without a whole lot of live practice reps and practice periods day after day after day for him to get confidence in that thing, I don't think this is a great time or a great week to go ahead and do that."
The Broncos' offensive line has sprung some leaks during their four-game losing spiral that's followed their 6-0 start.
In addition to Harris' injury, Ben Hamilton, the longest-tenured player on the roster, lost his starting job at left guard to Russ Hochstein, who inadvertently jarred the ball out of running back Knowshon Moreno's hands for a fumble at the goal line in Denver's loss to San Diego on Sunday.
McDaniels cautioned against thinking that Harris' return in two weeks will solve everything up front.
"It's one of those things where you can't say we expect it all to fix itself when one player comes back because then you've got the wrong mindset," McDaniels said.
McDaniels said safety Brian Dawkins (neck) should play Thursday, and that Simms remains Orton's backup.
Copyright 2009 by The Associated Press