CHICAGO — Matt Nagy emphasized Andy Dalton will reclaim the starting job when he is healthy, but the Chicago Bears have reversed course.

Justin Fields will be the quarterback moving forward for the organization.

Nagy announced the decision Wednesday morning after the team’s walk-through in advance of the afternoon practice. Fields will start Sunday when the Bears travel to Las Vegas to face the Raiders.

Dalton will be a full participant in practice and is expected to be the backup quarterback this week, but he’s been demoted.

“What needs to be understood the plan and process we had going into this was important,” Nagy said. “When Andy got hurt with his knee, that sped the plan up. I have always said from the beginning, we’ll know and he’s done everything to show us he’s ready for this opportunity.”

Nagy said things were fluid and the staff made the decision in the days following Sunday’s 24-14 victory over the Detroit Lions. Dalton suffered a bone bruise in his left knee during the second quarter of the Week 2 victory over the Cincinnati Bengals, and that opened the door for Fields, who probably wasn’t going to sit on the bench long.

The Bears (2-2) dragged out a quarterback decision last week before playing the Lions when Fields completed 11 of 17 passes for 209 yards in a 24-14 victory. It was a big improvement over the disaster the week before in a loss at Cleveland.

“Not just the last week or two, this whole entire time we’ve see incremental growth,” Nagy said. “This isn’t something that happened just right away. He’s earned it. He’s worked hard. There’s a lot of discussions that go into this.”

Fields has completed 25 of 52 passes for 347 yards with no touchdowns and two interceptions on the season with a passer rating of 53.9. He’s been sacked 12 times but nine came in the Week 3 loss at Cleveland and the Bears made significant adjustments to their offense in preparation for the Lions, leaning much more on the running game and moving the quarterback under center.