Imagine, the fielder runs towards the ropes trying to stop a six, and catches the ball right near the ropes. But his momentum carries him outside the boundary. So, to stop a six, he throws it up in the air, before his feet touch the ground outside.
So far, this is something many fielders have done.
But, suppose his throw of the ball is not strong enough , so the ball after going up, comes down and is still falling down towards the ground outside boundary. So, the fielder just jumps up and while in the air, catches the ball and throws it back up. When the ball comes down, he does it again. He keeps doing that, juggling the ball while ensuring he is in the air , each time he catches the ball and throws it up, till his teammate who is inside the boundary reaches near the rope. Then he can jump up a final time , catch the ball while in the air and throw it back to his teammate's hand who is inside the boundary. So, even though the player did touch the ground outside the boundary multiple times , he only did so BETWEEN each touch of the ball, and never WHILE being in contact with the ball.
Would this catch be legal? Can he keep on juggling the ball in such a fashion, till his teammate comes to help and complete the catch ?
As far as i can tell, there is nothing in the rules that forbid it.
His last touch with the ground BEFORE his first contact with the ball was inside the boundary area, and at no point was he in contact with the ball WHILE he was touching the ground outside.