Which sentence uses a dash or dashes correctly?

After a split second of hesitation he was briefly unsure of himself— the baseball player leaped for the ball.

After a split second of hesitation—he was briefly unsure of himself the baseball player leaped for the ball.

After a split second of hesitation—he was briefly unsure of himself— the baseball player leaped for the ball.

After a split second of hesitation—he was briefly unsure of himself— the baseball player —leaped for the ball.