We've been on Peyton Manning Arm Strength Watch for a few weeks now, and this is probably the worst sign yet, from Albert Breer of NFL Network:

Got this text from a veteran scout a few minutes ago: "Peyton Manning can't throw the ball anymore." I'm reserving judgment, but ... — Albert Breer (@AlbertBreer) September 23, 2012

Manning played decently yesterday, leading Denver back from a big hole against Houston to make it competitive late.

But the stats on deep balls this year are still horrid. On passing attempts of 20 yards or longer, he's 0-5 with 3 INTs.

Whispers of Manning's weakened arm leaked out over the summer, and the first three weeks have done nothing to quell those concerns.

But there's reason for hope.

He just sat out an entire year after undergoing four neck surgeries, and logic suggests that he still has a way to go to work himself back into game shape.

Also, it's not like having a weak arm makes him horrible. The Broncos are still scoring points, and Manning is mentally sharp enough to find ways to move the ball without his full arsenal of throws.

If Manning isn't 100%, it means the Broncos can't be the juggernaut that SI, ESPN, and others thought they might be. It doesn't mean they won't be competitive.