The Lionesses were in real danger of Spain going 2-0 up as VAR judged Keira Walsh to have handled the ball in the box as Mariona Caldentey's shot went past her.
But the Manchester United goalkeeper did brilliantly to get down to her left to deny Jennifer Homoso.
Earps roared in celebration as her teammates ran to her as the Lionesses star stopped Spain from running away with the game.
It appeared as though she screamed 'f*** off' after saving the spot kick.
Spain's Olga Carmona put her country in front as both side's looked to achieve World Cup glory for the first time respectively.
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The Real Madrid star capitalised on Lucy Bronze losing the ball on the half way line.
Penalty hero Earps was inches away from saving it with an outstretched hand.
But the ball slotted past her into the bottom corner, leaving the England glovesman visibly frustrated.
Earps denied Spain in added time, too, blocking Ona Batlle's shot at her near post with an outstretched foot to send the ball behind and out of danger.
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Earps continued to make more brilliant saves, but England could not find the breakthrough at the other end as Spain won 1-0.