"I had to do what was best for me and what would make me happy. For the year 2009, I will be here at Clemson University," he said.
After a thunderous applause from those gathered in attendance, the former five-star ground gainer said it was his gut instinct more than anything else that led him to his decision.
But what may be more amazing than the announcement itself considering most people figured he had one foot out the door of his Clemson apartment, is that nobody on the team seemed to have a clue what was coming.
Even the projected starting quarterback headed into spring practice in March, Willy Korn, was in shock.
"We had no clue," he said. "None of us had any idea. I thought for sure he was going to the NFL Draft. "When we heard it all it was comparable to running down the hill or something. I'm still kind of shaking after the fact."
Spiller also finally revealed where the NFL Draft advisory board said he would be drafted, had he elected to leave Clemson a year early.
"The letter came back 'first round'," he said. "That was the hardest part. You really start thinking to yourself. But I really had to take all the emotions out of it really and do what was best.
"I talked with Coach Swinney about the situation I was in. If he was here or not I'd probably still be back but he helped me weigh the pros and cons. We just sat down and talked man-to-man and we supported my decision no matter what."
While Spiller's projection from the advisory board, which was under the subject of much debate in recent weeks, came back with a first-round grade, it didn't state which part of the first round he would likely be drafted.
"That's not how it works," he said. "They just said the round and it was the first but it doesn't matter. I'm going to get to work. I'm not going to take any days off and do what I can to better myself so I can mature more.
"No one knows [where I'll end up being drafted next year.]"
And Spiller also said another major factor was looking back on his time at Clemson with no second-guessing.
"I didn't want to leave here with regrets," he insisted. "I wanted to look back and say, 'you know what?' Even though everybody else thought I should go, I came back and that was the right decision."
Spiller, who was visibly emotional during the announcement, was matched in the moment by Clemson head coach Dabo Swinney afterwards.
"Nothing surprises me with C.J.," he said. "Like I've always said, C.J. Spiller is his own man so this does not surprise me one bit. He's going to be the first running back in the history of Clemson to be a first-team All-ACC selection while also making the Dean's List. How about that?
"Lets go ahead and kick-start the Heisman Campaign. I'd like to personally do that right now because he's a 10-star recruit."
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