In the main event of tonight’s UFC Fight Night in Las Vegas, Frankie “The Answer” Edgar dominated his old nemesis BJ Penn en route to a merciful third-round TKO stoppage in their featherweight encounter.

Edgar, a former lightweight champion, had previously defeated Penn twice at the 155 pound limit. Both bouts were five-round decisions which lasted the final bell.

That was not the case tonight. The bout was Penn’s first at featherweight, and the former lightweight and welterweight champion looked weak and confused from the opening bell, fighting out of a strangely straight posture with a slow jab. Edgar darted in and out for punching combinations — also landing takedowns for ground-and-pound.

As the bout progressed, Edgar, a former wrestling standout at Clarion University of Pennsylvania, took Penn down at will. Penn, the first American to become a Brazilian jiu-jitsu world champion at black belt, managed no offense on the ground.

In the third round, after a brutal series of punches and elbows, referee Herb Dean mercifully stopped the bout.

Edgar would remark after the bout, “It’s a bittersweet victory… I almost feel bad about it.”

Penn, 35, of Hilo, HI, was a +385 underdog — with the line as much as ten to one at one point. He announced his retirement after the fight. His career ends at 16-10-2.

Edgar, 32, of Toms River, NJ. was a -465 favorite. His career record rises to 17-4-1.

At UFC Fight Night Edgar vs. Penn 3, Frankie Edgar defeats BJ Penn by TKO (punches and elbows) at 4:16 of round three.