I haven't seen you swing the club, but my educated guess would be is that your left hip isn't rotating with the lateral & rotation movement of the backswing. This is stopping you from getting your left knee behind the ball, your weight to the right side ... that is what's wrong (I think). This ends up being a reverse pivot position.

To fix it is quite easy ... as you turn right and rotate back during the backswing, turn your hips and left knee as well. You should end up with your left knee behind the ball, your hips are turned 45*, your right knee is flexed ... (that's what the solution is)

To drill this movement turn a club upside down, so you're holding the clubhead in your left hand. Put the butt of the club where the ball should be. Okay? Now, ROTATE the hips and the left knee at the same time as your torso ... get the left knee behind the shaft line, your weight all the way accross to the right. Your back facing the target ...

Hope this helps you.

__________________
Golf is easy ... once you know how.
Graham Arnott, teaching professional
Kelrosa Golf Studios
www.kelrosagolf.com
Class 'A' PGA Member
Full Member: World Golf Teachers Federation (GB&I)