My only comment would be to not place your subject in the centre of your image. It makes for a very static image. Following the "rule of thirds", I would have placed this guy on the right thirds line giving him space to move into on the left side of the picture. I find this approach makes for an image which is a bit more dynamic.
Just guessing, but the "line" looks like there was an out of focus piece of grass or some other vegetation closer to you in the way of your image. I have had this happen to me on occasion. Frustrating, but, as you found out, not much can be done about it unless it can be cropped out without affecting the composition of the image.
WesternGuy