Baseball- hmmmmmm. One can try a green print that looks like grass; some kinds of batik go rather well too. There is fabric that looks like sand and could be taken for dirt. I just ordered fabric for basketball themed quilt and ordered a large print and a smaller one for contrast with batik added. A good site for fabrics is called e-Quilter and the neat thing is that if you find a print, when you get the close up, there is a button that you can hit with your mouse when you scroll over the print and find a coordinating color in the print that you want to accompany it and it will call up all fabrics within that color range. Really cool! Good luck and hope this helps. You just have to be bold and go for it and it will always come out OK if you follow your instinct. Just remember - there are no rules in quilting!