You probably don't want to have to have a box (with you inside) lugged onto a ring, shown empty and have to be revolved for everyone to see it is empty, then you appear and the big box has to be lugged away before the main event can take place. And there's all those ringside ropes to navigate, besides.
This is the perfect place for Wizard magic and thinking outside the box. Try a parachute appearance. A bunch of assistants bring a small parachute into the ring (cut to the size requirements of the ring). They stand all around it and lift it up, catching air and lowering it to the ground. This is done three times and on the third time, they seem to have "caught something" under the cloth. The form under the cloth rises to its feet and the parachute is whipped away to reveal the Illusionist. I assume you'll want to continue with more magic than that, so the assistants bundle away the parachute and the performance continues with whatever else you had in mind. That's Wizard Magic! No box!