Before I'd do much of anything, since you say your pitch/span has not changes, look at your diet. Have you slowed down on fluids ? Started anything different ? Reason I ask, I drink WAY to much coffee, my thumb would swell into the second game. I switched to water and the thumb does not swell at all, now.
I also noticed I'd eat a bit more sweets at times and that would make my thumb swell a bit, so, if you have changed or not drinking enough fluids, IMO, that might be your problem.
Just guessing. Hope this helped.
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az guy aka: R & L Bowlers Pro
rlbowlerspro@cox.net
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