The Seahawks will start Matt Flynn at quarterback in their first preseason game.
Seattle faces the Titans on Saturday and Flynn will work exclusively with the first-unit offense for the remainder of the week.
Russell Wilson will be the backup and Tarvaris Jackson isn't expected to play.
"At this time,I think that I can make a little bit of a shift," Carroll said. "And cut down his [Jackson's] reps so that we can get a really good look at Matt and at Russell. To make a big decision like this, it's about the information you gather, and I want really, really good information coming in so we can make a really clear-cut choice as we do it."
Flynn signed a three-year, $26 million deal with the Seahawks in the offseason after serving as Aaron Rodgers' backup for the Packers over the past four seasons.
Matt Flynn To Start For Seahawks In Preseason Opener