Tonight at UFC 158 in Montreal, UFC welterweight champion Georges St. Pierre defended his title against bitter rival and former Strikeforce champ Nick Diaz. GSP controlled the fight and won by unanimous decision. Here's what our own Brent Brookhouse about the final round in the bout, and you can check out the full fight video highlights above.

Round 5 -GSP landing the jab and now Diaz tries to come forward and he does land a good left. GSP with a hard jab. They clinch and Diaz lands a knee to the body, GSP lands one in return. They're trading knees to the body in the clinch. GSP landing two punch combos. Diaz throws a head kick and GSP lands a leg kick sweeping Diaz to the mat. GSP on top now with Diaz looking for a kimura. GSP's arm is free, Diaz rolls, GSP stays on top and lands some punches and now a knee to the body. Diaz manages to escape. GSP with the jab. Diaz with some body shots in the clinch. Leg kick by GSP and he misses a head kick. GSP with a big takedown with under a minute left. GSP lands a hard elbow. GSP flurries to the end. Diaz raises GSP's hand after the fight ends.10-9 GSP for the clean sweep.