The two traded high-scoring blows in an epic final before Bells lost her pulse late to ensure Fanning, 30, held on to secure his first Rip Curl Pro title in 11 years.
He had crashed out early at the season-opening event on the Gold Coast, but was back to his ominous best this week as Bells turned on breathtaking surf. And he made the early pace in yesterday's final.
But Slater, the 40-year-old American, threw down the gauntlet, pulling off a perfect 10-point full-rotation aerial that he had no right to land.
"That was so hectic," Fanning said.
"I was freaking. I started off with a nine and then he throws a Hail Mary and gets a 10 and I'm thinking, 'Oh here we go, come on'."
But Fanning, a two-time world champion, responded with a 9.70 to reclaim the lead amid a series of strong counter-attacks from the world's greatest surfer.
Slater's second placing returned him to No.1 in the world.
"Even when he had the nine and eight-something, I had a feeling I was in it.
"I felt like something good was going to come my way and it started to. I had one more chance and that was about it.
"I knew it was going to be a bit of a struggle with the waves out there, with the long intervals and long lulls, but that's just the way it goes."
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