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www.tennisonly.com.au
This reviewer
From: Sean - CA, United States. July 10, 2022
I just noticed said this
"The only big problem I have with the shoe is the 'attack angle' of the back heel support towards the achilles. It ruined the shoe until I decided to razor blade the section and take a chunk out of it (half an inch wide or so) to prevent myself from getting blisters. No idea why adidas went with such an aggressive angle on that heel support. If they just went straight up with it I think the shoe would be perfect."
That appears to be the same problem I have had so far...