Again (so it doesn't get lost in this busy thread)...the big thing that I'm seeing, is that you use AF-S, rather than AF-C. So it's very likely that you're focusing on something (maybe the subject) but then something moves (composition or subject) and because you're in AF-S, the focus is likely locked...and thus, the result is an out of focus photo.
It could also be that your focus (if in single point mode) isn't hitting on the subject. Auto area mode my help, but being a 'auto' mode, it's not guaranteed to catch the subject. But it may be worth a try.
^^^ THIS!
Reading through the thread, I didn't notice anyone point this out... but this was my immediate concern.
Your shutter speeds appear to be fast enough.
Blur can be caused by motion (either camera motion or subject motion) if the shutter speed is not fast enough. Your shutter speeds appear to be fast enough to sufficiently "freeze" your subject. It is unlikely the blur is caused by motion.
I also noticed a few comments about focus points... but even if you picked a specific focus point, accurately targeted that point on your subject, and allowed focus to lock, there's STILL the problem of a moving subject changing focus distance.
The camera has two different focusing priorities and modes.
AF-S (AutoFocus-Single) mode tells the camera you want it to activate the auto-focus system UNTIL it can lock focus, and then stop worrying about focus. That means once the camera locks focus, it's done (at least it thinks it's done). The subject can move but the camera is not monitoring the subject for movement. It presumes the subject is stationary and once the focus locked it should never changed until you release the shutter.
AF-C (AutoFocus-Continuous) mode tells the camera to never give up on focus... even if it achieves focus lock, you're telling the camera that the subject is not necessarily remaining still and the focused distance may be changing. The camera will continuously re-evaluate and adjust focus in this mode.
But there's one MORE thing you need to look at... that's the difference between "focus" priority and "release" priority.
"Focus" priority means the camera insists that before it will release the shutter, it MUST be able to confirm that at least one focus point was able to "lock" focus... on something (it may not be the "something" you want if you're allowing your camera to pick any focus point.) As long as it can confirm that focus locked on something... it will allow the camera to release the shutter. It will actually block the camera from releasing the shutter if it is not able to lock focus.
"Release" priority reverses the focus behavior. This mode says the camera WILL release the shutter WHEN you fully press the shutter button. It will do this WHETHER the camera was able to lock focus on anything or not.
Here's a link to a good article which describes this:
The Nikon Companion: Understanding What Focus and Release Priorities Do During Autofocus
That's a lot to digest:
- Is the camera operating at appropriate shutter speed to "freeze" moving subject and/or to avoid blur caused by camera movement while shooting?
- Did you allow the camera to pick any focus point or did you require that it use a specific focus point?
- Was the camera in Single-servo focus mode (AF-S) or continuous mode (AF-C)?
- Was the camera in focus priority mode or release priority mode?
And then there is one last thing. Sports and action photographers will often exploit the continuous/burst mode shooting style because they KNOW that even when you think through everything, haven't ignored any of the important points, and take the shot... there's still a margin of error in the camera. Many shots that you feel SHOULD be tack-sharp will not be -- not through any fault of you or your lens. They burst many shots to improve the odds that at least one of them will be a keeper.
The benefit of your camera is that it offers a LOT of control... the down-side is that means there are perhaps more options than you realized are available.