Karel Istaz, best known by his ring name Karl Gotch, was a Belgian-American professional wrestler, amateur wrestler, catch wrestler, and trainer.

Catch wrestling is a classical hybrid grappling style and combat sport. It was popularised by wrestlers of travelling funfairs who developed their own submission holds, or "hooks", into their wrestling to increase their effectiveness against their opponents. Catch wrestling derives from various different international styles of wrestling including several English styles. The training of some modern submission wrestlers, professional wrestlers and mixed martial artists is founded in catch wrestling.