Chicago Bears starting quarterback odds: When will Justin Fields replace Andy Dalton? Week 4 vs. Lions could be perfect spot

Chicago Bears coach Matt Nagy has made it crystal clear that veteran Andy Dalton will be the team's starting quarterback for the season opener on Sept. 12 at the Los Angeles Rams, but it's just a matter of time before Dalton takes a seat for the future of the franchise in rookie first-round pick Justin Fields. SportsLine offers odds on when Fields may take over – for non-injury reasons.

The Bears won their preseason opener this past Saturday, 20-13 over Miami, but Dalton and the first-team offense were inept; Dalton played the first two series. Fields didn't play that well right after taking over in the second quarter but then flashed his talent in the second half. The No. 11 overall pick out of Ohio State finished 14-for-20 for 142 yards and a touchdown (rating of 106.7, which would have ranked No. 5 in the NFL last season) while rushing five times for 33 yards and a score.

Those are great numbers, but Bears fans well remember how good then-rookie Mitchell Trubisky looked in the 2017 preseason. Dalton will start again this Saturday vs. Buffalo and Nagy said Monday that Dalton will actually play more than he did vs. Miami but that he also wants Fields to get more time with Chicago's No. 1 offense against the opponents' starting defense.

Clearly it will depend on how the Bears are faring from a win/loss perspective for when Nagy makes the switch in the regular season. It's tough to see Chicago winning at the Rams as 7-point underdogs in Week 1. The Bears should then be favored in their home opener Week 2 against the Bengals but again solid underdogs Week 3 at Cleveland.

Thus, one would imagine the earliest Fields would get the call would be Week 4 at home vs. a bad Detroit team. Trubisky got his first start four years ago in Week 5 at home vs. Minnesota when the Bears were 1-3 entering. Then again, Dalton is a lot better than that year's Week 1 starter, Mike Glennon.

All things being equal, coaches would prefer to give a rookie QB his first start at home and preferably against a lesser defense. The Lions would qualify on both counts.

Chicago's schedule gets much tougher after that: Week 5 at Las Vegas, Week 6 vs. Green Bay, Week 7 at Tampa Bay, Week 8 vs. San Francisco and Week 9 at Pittsburgh before the bye in Week 10.

Via SportsLine NFL odds When will Justin Fields get his first NFL regular-season start (non-injury reasons)?

• Weeks 1-3: +400
• Weeks 4-6: Even
• Weeks 7-9: +250
• After Week 10 bye: +1500

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