Last season I had a pitching session and the pitching coach told me to grip my 4-seam fastball with my index and middle fingers closer together, probably a couple millimeters apart as opposed to the good half-inch at the farthest part I had before. He said this would give it tighter spin and therefore make the ball go straighter. This worked well, but yesterday I was looking at pictures of pitching grips and saw this picture of Cole Hamels gripping a fastball (I’m pretty sure).
I’m pretty sure this is his fastball. This isn’t a huge issue I know, just wondering. Is it his fastball, and if it is is it just a grip with his fingers spread apart? Does this create more movement on the fastball (running fastball?).