Robbie Lawler showed his “Ruthless” side Saturday night, successfully defending his UFC welterweight title with a fifth round finish of Rory MacDonald at UFC 189.

Lawler, fighting for the first time since he won the title from Johny Hendricks, found success early in the rematch with MacDonald before the challenger battled back. However, in the final round, the champion landed a shot to the already-injured nose and earned the finish shortly there after.

“It was an accumulation of a beat down,” Lawler said. “If you stay in my face, I’m gonna knock you out.”

MacDonald, who lost via decision the first time these two squared off, landed a head-kick in the middle stages and rocked Lawler. He followed up, but was unable to land the final blow.

“I showed everyone I’m a true fighter,” Lawler said. “I come to fight. No matter what happens, I keep coming and I am gonna knock you out.”