soften the rest... as in use the blur. unless u wanna do a lasso around the eye, give a few cm radius around it, then sharpen, then do history brush around the lasso area, then will look quite weird sometimes.
Apply Unsharp Mask filter to Background layer. Duplicate layer, apply same filter a couple of times more. Add Layer Mask to create a black mask to layer. This layer will conceal the sharpened layer. Use Brush tool, set foreground colour to white and paint away areas that need sharpening. Ta da!