NFL preseason betting storylines to follow

The NFL's 2018 season will kick off on Thursday, September 6. AP Photo/John Locher

The NFL preseason has arrived, a monthlong warm-up for the regular season that almost always has a significant impact on the betting odds.

Big-name quarterbacks who missed the end of last season to injury are returning, including Green Bay's Aaron Rodgers, Houston's Deshaun Watson, Indianapolis' Andrew Luck and Philadelphia's Carson Wentz. Quarterback competitions in Arizona, Cleveland and New York with the Jets could leave rookie signal-callers in starting roles. And you can count on unfortunate injuries to key players that change a team's outlook and the landscape of its division.

Here are some of the storylines ESPN Chalk will be following in this file that will be updated throughout the preseason:

Andrew Luck's progress

In April, the Colts opened as low as 1-point home favorites against the Cincinnati Bengals in Week 1. As optimism grew about Luck's recovering shoulder, the line moved to Indianapolis -3, and the Colts' season win total also grew.

Luck was sidelined last season with a shoulder injury, and the Colts went 4-12. He began throwing again in the spring and reportedly will play the first quarter of the Colts' preseason opener against Seattle.

"If he does anything in that first quarter, looks decent, we'll probably go to 3.5," Westgate SuperBook oddsmaker Ed Salmons said of the Bengals-Colts Week 1 line, "because we would view the Colts as a better team than the Bengals."

The Colts' win total opened at 6.5 (-130 under) in late April and attracted respected action at the Westgate. The number had been bet up to 7 as of Thursday.

"If [Luck] plays better in the preseason, that number is probably going to go to 7.5," Salmons said.

The Colts, at 60-1, have attracted the fewest bets to win the Super Bowl of any team at the Westgate.

Buying the Browns?

There are mixed opinions on Cleveland. Some see a team poised for significant improvement. Others struggle to get past the Browns' 1-31 straight-up record the past two seasons -- not to mention a putrid record against the number in 2017.

After opening at 5.5, the Browns' win total is up to 6 (-130 under) entering the preseason.

"The public has been hard on the under on the Browns," Salmons said. "One of our house players made a significant bet on the over. I really like Cleveland this year. I bumped the number up to 6 and really think that they'll go over that number."

Experienced quarterback Tyrod Taylor, acquired this offseason from Buffalo, is expected to hold off No. 1 pick Baker Mayfield for the starting nod and the right to orchestrate an upgraded offense.

Notable Week 1 line movement

Buffalo Bills at Baltimore Ravens (-6, 40.5): Baltimore opened as 3-point favorites, but the number was bet up all the way to -6 in late July.

"The Bills are like last year's Jets," Salmons said. "We started at 7 under with their [season] wins, went to 6.5 under, now we're 6 under. That's been mostly wiseguy money driving that down. And it makes sense."

Atlanta Falcons at Philadelphia Eagles (-3.5, 46.5): This line got as high as Eagles -5.5 in early May but came back down in July at the Westgate.

"We had a guy who we respect a lot make two big-sized wagers on Atlanta at +4.5 and +4," Salmons said.

Philadelphia quarterback Carson Wentz, who is recovering from a knee injury suffered in December, may not play during the preseason, and his status for Week 1 remains up in the air. If Wentz sits out, backup Nick Foles, who led the Eagles to a win over the New England Patriots in the Super Bowl, would be expected to start.

Tampa Bay Buccaneers at New Orleans Saints (-9.5, 49.5): The line opened at New Orleans -7 and was adjusted up 2.5 points after Tampa Bay quarterback Jameis Winston was suspended for the first three games. Veteran backup Ryan Fitzpatrick is expected to start for the Bucs against the Saints. The total has come down from 52 to 49.5.

Cleveland Browns at Pittsburgh Steelers (-5, 47.5): The point spread opened as high as Pittsburgh -7 but has been bet down to -5 this week.

Super Bowl odds and over/under movement