Justin Fields showed dramatic improvement on Sunday in his second NFL start, a 24-14 Chicago Bears win over the Detroit Lions.

It wasn't enough in Matt Nagy's eyes to secure the starting job. The Bears head coach told reporters on Monday that when healthy, Andy Dalton remains Chicago's full-time starting quarterback.

"We've gotta see where Andy's at health-wise," Nagy said. " ... When Andy's healthy, he's our starter. Justin's the 2."

Dalton suffered a knee injury during Chicago's Week 2 win over the Cincinnati Bengals and hasn't played since. Nagy said after that game that Dalton would remain the starter when healthy and is sticking with that decision after two starts from Fields, whom the Bears traded up to select with the No. 11 pick in April's draft.

Fields improves week over week

Fields struggled in a Week 3 start against the Cleveland Browns. He was sacked nine times and completed 6 of 20 pass attempts for 68 yards in the 26-6 loss. He was markedly improved on Sunday in his first start at home.

Fields completed 11 of 17 pass attempts against the Lions for 209 yards without a touchdown and an interception on a deflected pass. He completed deep throws downfield. He took one sack. Chicago never trailed in the game. It was the kind of progress a team likes to see out of a rookie quarterback.

But for Nagy, Dalton is still the guy when he can go. The Bears hope to know more about Dalton's injury status by Wednesday. They face the Las Vegas Raiders on Sunday.