A lot of the time I hit my topspin single b/h pretty well, usually when I have more time to prepare. What I'm beginning to find recently, as I play better players, is some of that prep. time is disappearing and I get caught hitting either with my weight on my back leg, but feet sort of in the right position or more often with an open stance and my left leg nearer the ball than my right, although I get my shoulders round enough to get away with it. The result is that rallies are breaking down too often off my backhand side as I obviously lose power with these errors and so fall out of the rally. It tends to happen later in matches so it may be a fitness thing, but I don't make similar errors off the f/h side later on and don't actually feel tired after a couple of hours. I've resorted to hitting more slices later in the game as a result, which keeps me in points but limits the attacking options. Anybody know of any tips / drills that would help me with this - a split step maybe ... All suggestions welcome, thanks.