If it is a normal club, new grip, and you are still having problems, it probably is Arithmophobia. There are common issues with this. It could be the distance you have to hit the ball to, that makes you take the 8i out (150 for instance), and that is your phofia number...less likely because if you were 151 to the pin then you wouldn't have this problem. Most likely it could be the "8".

"Like all fears and phobias, numbers phobia is created by the unconscious mind as a protective mechanism. At some point in your past, there was likely an event linking numbers and emotional trauma..."

So maybe in your past you had a real pressure shot in a match that you had to hit the 8i to and failed, failed so bad as to create this phobia. If this is the case, face your fear head on. Play an entire round with just the 8i and putter. I bet you can do pretty well and will be amazed at what your score could be...I always joke that just about every par 5 from the white tees are just three 8i's.

If you STILL are having problems, let's take drastic measures here. Buy a matching 7i. Cut the shaft to 8i length, and have the faceangle bent the same as the 8i. There you go. Just make sure you know which 7i you are pulling out (put a piece of tape on top of the grip to be sure)...

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I'm a golfaholic, no question about that. Counseling wouldn't help me. They'd have to put me in prison, and then I'd talk the warden into building a hole or two and teach him how to play. ~Lee Trevino