In 2010, the infamous Jabulani balls for the World Cup in South Africa transitioned from turbulent to laminar flow between 50 and 45 miles per hour, right at the speed for corner and free kicks. The transition between these different types of flow causes even more drag on the ball, which caused the Jabulani to wobble in the air and drop in ways that players weren’t expecting.
On the other hand, replicas (sometimes called training balls or gliders) are designed to be just like the official match balls but are much cheaper. Their panels are often stitched rather than thermally-bonded and are made of a different material. However, they’re not necessarily less durable than official match balls. So, they’re the recommended option for most players. https://www.youtube.com/watch?v=j2Xn84L3Kcs
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