Mackenzie Dern defeated Gillian Robertson via unanimous decision to retain the strawweight championship in the UFC 330 co-main event Saturday night at Xfinity Mobile Arena in Philadelphia.
The judges scored the fight 49-46, 49-46, and 48-47 in Dern's favor.
Dern faced minimal adversity in her first title defense. She dominated Robertson throughout most of the fight, outstriking the challenger on the feet and controlling her on the ground.
Dern attempted a tight rear-naked choke in the first round, but Robertson survived.
Robertson's best round was the fifth, as she finished the fight on top of Dern and landing ground-and-pound. But it wasn't nearly enough to swing the judges' scorecards.
Dern became the 115-pound champion with a unanimous decision win over Virna Jandiroba at UFC 321 last October. The 33-year-old is now riding a four-fight winning streak.
Robertson challenged for a UFC title for the first time. The 31-year-old Niagara Falls, Ontario, native had won five in a row coming in.
