The judges scored the bout, 30-27, 29-28, 30-27 all in favour of the Canadian.
With so much on the line for both guys, Ellenberger was largely ineffective as the fight failed to live up to the hype.
It was a measured start by both fighters with MacDonald working behind his jab, utilizing his reach advantage and controlling the distance of the fight. Ellenberger was looking to explode with his shots, while MacDonald continued to fire his jab, stinging Ellenberger.
Ellenberger was unable to get on the inside with his striking and resorted to looking for the takedown, but MacDonald was equal to the task, shutting down the moves, effectively neutralizing Ellenberger's attack with his footwork and jab.
Ellenberger tried to pick up the pace in the final round, needing a finish, but much like the previous two rounds, he was largely ineffective, only able to land glancing shots when he got inside MacDonald's reach.
Inside the final minute, Ellenberger landed a takedown, putting MacDonald on his back, but it was too little too late as MacDonald moved one step closer to a title shot.
The victory was MacDonald's fifth straight, but whether he will put out the challenge to fellow Tristar teammate and UFC welterweight champion Georges St-Pierre or jump ship to middleweight remains to be seen.
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