Pink to the Rescue -- Singer Saves Puppy from Certain Death!!!

P!nk just came through with a canine Christmas miracle -- shelling out $5,000 to pay for emergency life-saving surgery on a puppy that had been tossed in the L.A. river and left for dead.

Sources tell TMZ ... P!nk was surfing the Internet recently, when she stumbled upon a story about a puppy that had been thrown off an L.A. overpass ... and suffered 3 broken legs when it landed in the L.A. river.

We're told the dog was in bad shape ... and required major surgery FAST ... or else.

That's when P!nk sprung into action -- contacting the Ace of Hearts animal rescue organization and offering to pay for any medical expense it took to save the dog's life.

$5,000 later ... the dog went under the knife -- and recovered!!