Playbooks

Near Close is the tightest alignment in the Near family, pulling both receivers inside the numbers while keeping the 21 personnel backfield stacked in a true Near look (fullback offset with the halfback directly behind the quarterback). Where standard Near sets push the split end out toward the sideline and the flanker to a normal wide alignment, Close compresses both wideouts down near the tackle box, which immediately changes how the defense has to align. Cornerbacks either walk down into press territory and give up leverage to the outside, or they stay off and concede a free release to a receiver who now has the entire field to work with horizontally. That compression is the whole point of the set, and it is why the Gadget tag shows up here: the alignment sells run first and lets you attack from an unusual look.
The personnel package is what makes this dangerous. With two backs and a tight end on the field, most opponents check into base defense or a heavier nickel, which means you are running Spacing and Post Drag against linebackers who have to cover ground in space. Post Drag out of Close is a genuine problem for man coverage because the drag starts inside the tackle box, gets an immediate rub off the compressed formation, and comes free across the middle before a user defender can flip his hips. Z Spot gives you the curl, flat, corner triangle from a condensed launch point, so the flat route breaks out into a huge void created by the tight alignment.
On the ground, FB Dive and HB Inside give you legitimate short yardage answers with both backs available, and PA Strong Flow ties the whole set together by putting the quarterback on the move off the same run action. The condensed receiver alignment means your blockers are already inside, so run fits get muddy for the defense, and the same look that produces FB Dive on second and one produces Post Drag for a chunk gain on the next snap. That is the sequencing advantage: nothing about the pre-snap picture tells the defense which one is coming.
Establish FB Dive and HB Inside early so the run action on PA Strong Flow actually holds linebackers, then go back to the play action later in the game when you need a chunk gain
Read the cornerback leverage before the snap: if both corners walk down into press, go to Post Drag and let the rub work; if they play off, take Spacing and hit the underneath layers
Hot route one of the compressed receivers to a streak or a fade when you diagnose single high man coverage, because the tight split gives him a clean inside or outside release with no help nearby
Use Z Spot on third and medium against zone, work the spot route first, then check the flat if a Cover 3 corner sinks with the corner route
Motion the flanker out to a normal split before the snap when you want to force a coverage declaration or turn Close into a more conventional Near look without burning a formation subbing
Do not live in this set on third and long, the compressed splits and lack of a natural vertical threat make it easy for a two high defense to squeeze everything short of the sticks