Instead of knocking an incoming spell aside, you can redirect it to a new target.
Benefit: When you successfully deflect a spell or ability using the Deflect Spells feat, you may choose to immediately spend a second point from your ki pool as a swift action to redirect the spell or ability to a new target, even though it is not your turn. The spell or ability’s maximum range must be long enough to go from the original attacker, to you, to the target you redirect it toward or the spell fails to reach the new target. You make any required attack roll to hit the new target, but all other affects are determined by the caster level and abilities of the original attacker.
Adventurer’s Handbook: Genius Guide Volume 1