Nice timing Paolo! Always neat to capture a frame right before they contact the water. I might boost the contrast and saturation a little. I would also consider a bit more sharpening of the head and a little cleanup of the water.
What a great pose/action on this duck. The head does need a bit of sharpening. I think since the reflection is less than ideal, I might try this in horizontal. I cropped, sharpened the head a tad and cleaned up the water. You could do much better with the original. Just somethin to think about.