You've got the right idea, in that you're going to use sp(tA), which will be the position of the player when striking the ball. Noticing that sp=0 when t=0, we can also say that this is the distance the player has traveled (as you had mentioned in your first post).
Now the trick will be to equate that to the correct value. This is where a diagram is very important, as it is in so many physics problems. I envision sitting on the sideline, with the goals on the left and right. The ball is in the lower left corner, and the player out in the middle of the field, a distance 2d in the xdirection from the lefthand goal line. The ball rolls out into the field at 45 degrees to the northeast. It travels a distance d in the ydirection according to the problem. How far did it travel in the xdirection? Do you see that the distance traveled by the player is now 2d minus this amount? Did your diagram help you see this?
As a physicist, it will help you a great deal to get into the habit of starting with a diagram. Details that can be difficult to envision in our heads become trivial when we see them in a picture with x and y axes.
