Most coaches leave their starters in for the majority of the first half, fine-tuning the offense and defense in preparation for the season opener.
Here's what we're watching for in Friday's games:
It's all about Blake Bortles. The Jaguars remain insistent that Chad Henne will open the season as the starter, but the coaching staff concedes the rookie is making it a tough decision. Can Bortles continue his success against the Lions' first-string defense?
Matthew Stafford was excellent last week in our first extended view of Joe Lombardi's offense, enjoying a surplus of weapons with wide receiver Golden Tate and rookie tight end Eric Ebron making plays. Can he keep it going against an improved Jacksonville defense?
We've been down this road with Stevan Ridley before. Is he back in Bill Belichick's doghouse after last week's red-zone fumble? Keep an eye, too, on the Patriots receivers. Julian Edelman and Kenbrell Thompkins were the starters last week, with Danny Amendola and Brandon LaFell in the third and fourth roles.
Eli Manning has averaged 3.06 yards per attempt in three preseason games. The adjustment to Ben McAdoo's West Coast offense can't be going any worse. The Giants will be searching for some sign of encouragement in the battle for the Snoopy Trophy.
Both Jets quarterbacks underwhelmed last week in Cincinnati. Because Geno Smith has to faceplant to turn this into a legitimate competition, the better story is in the backfield. Now that Chris Ivory is healthy, is he going to take carries away from Chris Johnson?
The Raiders' first-team offense has struggled mightily, in large part due to Matt Schaub's inability to power throws outside the numbers and down the seam. He's gotten little help from his offensive line or wide receivers, but his arm still looks shot. Will he continue to be outplayed by third-stringer Matt McGloin? If so, will the coaching staff be tempted to make an unexpected change in September?
Scott Tolzien and Matt Flynn are locked in a dead heat for the privilege of backing up Aaron Rodgers this season. If Tolzien proves to be the better option, will the Packers considering carrying just two quarterbacks on the roster?
Newly signed Santonio Holmes is competing with veteran Josh Morgan for the No. 3 receiver job. If the Bears were satisfied with Morgan, they wouldn't have signed Holmes. Let's see if Holmes is ready to contribute after it appeared that he lost a step or two with the Jets last season.
So why is Robert Turbin still ahead of him in the backfield pecking order? As gifted as Michael is, he hasn't stood out in preseason action the past two weeks.
The "Around The League Podcast" AFC Season Preview is here. You're welcome.