Rory MacDonald absolutely dominated BJ Penn tonight at ‘UFC On FOX 5’, claiming a clean sweep on the judges scorecards to confirm him as one of the very best young fighters in the sport today.

From the opening bell Penn pressed forward and looked to press MacDonald up against the cage, but MacDonald easily reversed him. Penn was able to push him off, but MacDonald again Slammed him into the fence and pushed his weight up against him.

They break free and start to to exchange. MacDonald looking good with an accurate punch, and not long after a solid leg kick that momentarily took Penn’s balance. The younger man then followed up with a slick Brazilian kick – starting low and then coming up high and it landed to the head, but Penn appeared unphased.

Good start for MacDonald, but Penn started to work his way into the fight, starting to measure up MacDonald for counter strikes.

Another brief clinch against the cage and again MacDonald is the stronger of the two, but they split up again.

Back to the striking and MacDonald looks very confident. He shows why when just moments later he lands a hard elbow to the head and Penn wobbles badly, clearly hurt.

MacDonald continues to press him and lands some solid shots, continually attempting the Brazilian kick without really making it count, and they clinch up giving Penn a chance to slow things down until the end of the round.

Penn tries to gain his respect early in the second round landing a good punch, but the much bigger MacDonald looks remarkably assured out there and stalks the former champion firing off excellent combinations of punches and kicks against the cage.

It’s looking grim out there for Penn and it gets worse when MacDonald crashes a hard kick into his mid-section that clearly has the Hawaiian hurt. Penn tries to cover up as MacDonald targets the spot again, then pours on the pressure with hurtful blows.

The referee is watching closely, but Penn isn’t going to quit and hangs tough. He’s getting a real beating though and his face is battered and bruised as MacDonald continues to pick him apart.

Changing things up MacDonald takes Penn down in the final stage of the round, but nothing much comes of the position.

In-between rounds the doctor takes a close look at Penn who’s face is a mess, but he’s allowed to continue.

Penn wisely tries to get the fight to the mat himself, but can’t quite get it. The pace of the fight has slowed a bit and there’s a lull, punctuated by just a few nicely placed shots from MacDonald.

The onus is on Penn to push the pace here, but he looks tired. Meanwhile MacDonald starts showboating a little which the crowd don’t like.

MacDonald lands a head kick, but Penn is ok. Soon after he lands a nice two-piece combination with authority.

Penn just doesn’t have the gas to mount one final push and MacDonald does the ‘Ali Shuffle’ and then bangs in a hard leg kick in the final moments of a fight he’s clearly dominated.

Credit to Penn for surviving a gruelling fight, but there’s no doubt about who the winner is here, with MacDonald claiming a unanimous decision victory (30-26 x2, 30-27).

This was the most confident, composed fight of MacDonald’s career and he showed clear improvements in his striking too. Based on this performance he’s now going to be on the fast-track to a title shot and the rest of the division better watch out.

As for Penn, MacDonald took the wind out of his sails early and he never recovered. There was a major size difference between the two men which only emphasized the fact that he really doesn’t belong at 170lbs, and if he does want to fight again it has to be at the division he once ruled, 155lbs.

After being handed another beating like this though you have to wonder whether the 33 year-old will once again fall into retirement.