Singer Sean Kingston owes his life to his quick thinking friends and 2 good samaritans who helped hold his head above water following a harrowing Jet Ski accident in Miami on Saturday.

TMZ spoke with Sean’s friend, Cassandra Sanchez, who was on board the Jet Ski with him when they collided into a bridge support.

Sanchez said the 21-year-old singer was racing friends who were on a 2nd Jet Ski in the coastal waterway between Palm Island and Star Island where Puffy Combs owns a mansion.

“Both jet skis pulled out of the dock at the same time and we were going so fast we just blasted past them,” Sanchez told TMZ. “When we turned a corner and crashed … they were so far behind us they didn’t even see us crash.”

Sanchez said as Sean was racing towards the bridge, she screamed out, “We can’t fit under there! Are we going to try and go under there? Sean stop!” But Kingston didn’t turn quickly enough and slammed into one of the supports under the short bridge.

Sanchez said she remembered waking up in the water in pain. Sanchez says, “[Sean] was coughing up blood, foam and pink stuff” … and when he finally opened his eyes, he kept repeating the words, “I’m hurting. I’m hurting”

She said her friends on the other jet ski raced over and tried to help out. Two boaters — one of them a coast guard officer — helped to hold Kingston’s head out of the water. He suffered severe injures, including a ruptured artery and a punctured lung.

Coincidentally, Kingston and his passenger were transported to the same hospital where I received my RN nursing degree — Jackson Memorial hospital. He is in very good hands there.

Kingston was stabilized at Jackson’s Ryder Trauma Center where he was hooked up to a ventilator and given blood transfusions to replace the blood volume that he lost. He is currently in stable condition in the intensive care unit.

Sanchez who visited Sean in the ICU after she was released said “he can’t really talk, but he is lucid and understands what’s going on.” Sanchez says doctors plan to keep Sean in the hospital for “a couple more weeks.”

TMZ reports that tennis star Serena Williams, who lives in Miami, visited Sean in the hospital yesterday.