Former UFC fighter came out of retirement to notch an insane slam knockout

This is an impressive way to come out of retirement.

Gerald Harris came out of retirement and knocked out Aaron Cobb at Legacy UFC 63 on Friday, more than three years after his last fight.

The fight was initially set to be a 185-pound welterweight bout, but Cobb weighed in at over 220, leaving Harris to chug water in order to put on enough weight to get to the 208 pound heavyweight minimum.

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And the 37-year-old needed little time, body slamming Cobb in the first round to end the fight. It was Harris's first bout since August of 2013.