Steve Gustafson of The Villages said he was trimming an oak tree outside of his house Friday when he heard his 9-year-old dog, Bounce, cry out in pain, the Orlando (Fla.) Sentinel reported Wednesday.
Gustafson said he looked to the source of the sound and saw Bounce was being held by the collar and shoulder in the mouth of the gator, which was attempting to carry her out into the water of a nearby pond.
"I just knew that my best friend was going to be dead," Gustafson said. "And I took off.
"For whatever reason, I don't know, I just yelled, 'you're not going to get her!' and just leaped on the gator ... just like you do some silly belly flop in a pool," the Iowa native said. "The only difference was I landed on top of a gator."
Gustafson said he was able to free Bounce from the reptile's jaws and carry her back to shore.
He said neither dog nor human suffered any serious injuries.
Gustafson said a trapper snared the alligator Sunday -- and he plans to have it processed and put it on display at his home.