Middleweight champion Anderson Silva will defend his title against countryman Thales Leites in the UFC 97 main event on April 18 at the Bell Centre in Montreal. The UFC made the matchup official on Sunday.

Silva, the sport’s resident juggernaut, will carry a nine-fight winning streak into the bout, as he makes the fifth defense of his 185-pound crown. The 33-year-old Brazilian last appeared at UFC 90 in October, when he retained his belt against Patrick Cote. Afterward, Silva was criticized for what many viewed as an uninspired performance, which ended 39 seconds into round three after Cote collapsed with a non-contact knee injury and was unable to continue.

Should Silva (23-4) defeat Letes, he will pass Royce Gracie and Jon Fitch in the record books for most consecutive victories inside the Octagon (he currently has eight). Since he arrived in the UFC in June 2006, the muay Thai specialist and Brazilian jiu-jitsu black belt has all but obliterated the UFC’s middleweight division, scoring decisive victories against one-time champion Rich Franklin (twice), two-time Olympian Dan Henderson and former King of Pancrase Nate Marquardt, among others.

Leites (14-1), meanwhile, has not competed since he submitted the one-dimensional Drew McFedries with a first-round rear-naked choke at UFC 90. Based out of the Nova Uniao camp, the 27-year-old Brazilian jiu-jitsu black belt has rattled off five straight wins since he dropped a unanimous decision to Martin Kampmann in his UFC debut in November 2006. He counts victories against Marquardt and Jose Landi-Jons among his 14 career conquests, nine of which have come by submission.

In the co-main event, former UFC light heavyweight champion and future hall of famer Chuck Liddell will collide with Mauricio "Shogun" Rua.

The once-unstoppable Liddell (21-6) has lost three of his past four fights and has not appeared inside the cage since his brutal knockout loss to reigning 205-pound king Rashad Evans at UFC 88 in September. Still, the 39-year-old striker wields a resume few can match, with multiple wins against UFC hall of famer Randy Couture, former light heavyweight champion Tito Ortiz and current Strikeforce light heavyweight titleholder Renato "Babalu" Sobral. He has also defeated Wanderlei Silva, Vitor Belfort and Alistair Overeem.

Rua (17-3) has endured a stunning fall from grace since he won the Pride middleweight grand prix in 2005. The flashy 27-year-old Brazilian last fought in January, when he stopped Mark Coleman on third-round strikes in a sloppy performance that was almost universally panned. That followed his submission loss to Forrest Griffin at UFC 76 and two subsequent knee surgeries. Still, his past accomplishments cannot be discounted. He holds a pair of knockout wins against Overeem and another against Quinton "Rampage" Jackson -- the only man to defeat Liddell twice.