Silva submitted the two-time Olympian wrestler 4:52 into the second round of the UFC 82 main event.
Henderson won the first period, though. After throwing occasional kicks during the opening two minutes, Silva lunged in for a punch and Henderson used a body lock to take him down.
The Brazilian was on his back for the rest of the round. He tied up Henderson's head, but the lifelong wrestler had room to throw short hammerfists from half-guard and side-mount.
Silva, 32, found his rhythm in the second. He cut off the cage and kicked to the body and legs of Henderson, who swung wildly in retaliation.
Following a brief exchange in the clinch, Silva stalked forward, nodding. His leg shot up for Henderson's head but missed. Next came another kick that hit to the body, and Henderson tried for a takedown. The 37-year-old veteran did not get it, but he worked his way back to the feet and again wrapped his arms around Silva.
This time, however, he couldn't take him down.
The clinch broke, and Henderson leaned in with a good right hand. His mistake was following with haymakers, which threw him off balance and nearly allowed Silva to land a knee from his dangerous Thai clinch. A knee did connect and hurt Henderson when Silva threw a left head kick, and a flurry ensued.
Henderson swung desperately. With crisper punches, Silva kept connecting on the feet until he stopped a takedown and resumed striking from the top on the ground. The fight slowed some as Henderson appeared to be recovering, but Silva hurt him again with about a minute left in the round.
Several right hands stunned Henderson, who gave his back. More punches and elbows followed before Silva secured a modified rear-naked choke.
"I needed to control the standup a little bit better," said Henderson, now 22-7. "I didn't pressure him that much. I should have kept him on the defense a little more. I kind of let him get his offense going by standing there a little too much. My game plan, I didn't execute it well enough I think."
Silva said he was not surprised that he had won with a submission.
"Not taking anything away from Dan Henderson -- he came, he fought very well -- but in my mind, the real champion other than myself that I have faced in the Octagon was Rich Franklin (Pictures)," said Silva, 21-4, who defended his middleweight title for the fourth time. "Not to take anything away from Dan Henderson, though."
Heath Herring (Pictures) (28-13) stormed out of his corner against Cheick Kongo (Pictures) (11-4-1). Kongo stood waiting, seemingly disinterested until a right hand had found his face. The 32-year-old resident of Paris staggered into the cage but soon executed a takedown.
In fact, Kongo scored several takedowns in the fight. Although he had out-struck Mirko "Cro Cop" Filipovic last September, he chose to engage Herring on the mat.
The strategy won Kongo the opening round. Despite absorbing that first big punch, he hurt Herring with strikes on the ground while the fighters traded numerous positions. Herring reversed twice, but Kongo kept winning the scrambles and inflicted more damage when he was on top.
In the second period, though, Herring took the top and did not relinquish it. That, perhaps, was the difference in the fight: Herring could get off his back, but Kongo could not.
The 29-year-old Texan moved from the north-south position to side-control, where he worked enough knees into Kongo's body to arguably take a second round that also saw him absorb his fair share of strikes. The third was similar. Herring escaped from underneath his opponent and mixed short elbows with more knees to Kongo's body.
One judge awarded the fight to Kongo 29-28, but the other two gave it to Herring 29-28 for a split decision.
"If I could have thrown [knees] to the head, this fight would have been over a long time ago," said Herring, who is now 2-2 in the UFC. "But here in the U.S., we don't have knees to the head."
Chris Leben (Pictures) (18-4) and Alessio Sakara (Pictures) (12-7) walked out of their corners ready to trade in a middleweight bout. The similar strategies were expected, and the result might have been equally predictable.
Sakara, a 26-year-old Italian training at American Top Team in Florida, had the technically superior boxing. He punched in combinations and connected more often than his freer-swinging foe.
Leben, 27, has a chin, however, and he hits hard. The chin lets him throw until he lands, which he did with a pair of left hooks behind Sakara's right ear midway into the round. Sakara folded to the mat, and Herb Dean (Pictures) stopped the fight at 3:16.
"He actually hit a lot harder than I thought," Leben said of his opponent. "His footwork and movement was really well. He caught me with a couple clean shots that actually hurt. It takes a lot to hurt me, so more power to him. That's exactly what I did. I put him in the blender. I took him in the deep end. I said you want to swing, let's swing."
Yushin Okami (Pictures) (21-4) ruined the return of former 185-pound UFC champion Evan Tanner (Pictures) (32-7). After two minutes of tentative boxing, the Japanese middleweight contender threw a one-two that sat Tanner down. The 37-year-old veteran recouped fairly quickly but mounted no significant offense in the round.
Okami, 26, continued his typically patient approach in the second period. Meanwhile Tanner looked out of sync on the feet -- understandable since this marked his return to fighting following a two-year absence from the cage -- and started eating more straight lefts as the round wore on.
The end came against the cage. Caught in the Thai clinch, Tanner tried to throw a right hook to the body. The punch gave Okami just enough distance to deliver a knee to Tanner's chin that dropped him, and referee Mark Matheny called the fight 3:00 into the round.
Jon Fitch (Pictures) improved to 8-0 in the UFC and 16-2 overall with a hard-fought win over Chris Wilson (13-4).
A 30-year-old welterweight who trains at Team Quest in Portland, Ore., Wilson won the first round in what was his UFC debut. He stuck a good right hand in Fitch's face and also connected with a jumping knee and a kick to the body.
"He's a long opponent, very good hands," the 30-year-old Fitch said afterward. "A lot of speed."
Fitch finished two takedowns in the first period and also took the top position off a scramble early in the second round. He passed to side-mount and mount before Wilson worked him back into the half-guard. Although Fitch failed to hurt his opponent, he controlled the ground game and earned the round.
The fighters traded for the first three minutes of the last round. Fitch, fighting out of San Jose, Calif., landed with a left hand and a right after Wilson had thrown another kick into his body. Another right hand then scored for Fitch, who may have sealed his win with a single-leg takedown. Regardless, Wilson was game, as he worked on a triangle choke until time expired.
All three judges awarded Fitch the fight: 30-27 twice and 29-28.
"I'm ready to fight for that title, whoever's got it," Fitch said. "Serra, St. Pierre -- whoever the best man is, I want to fight them. Once you have that belt, every fight you have is going to be the toughest. That's where I want to be."
Arlovski, Koscheck and Sanchez Win on Undercard
In what could be his final fight in the Octagon, former UFC heavyweight champion Andrei Arlovski (Pictures) (12-5) stopped the previously undefeated Jake O'Brien (10-1) at 4:17 into the second round.
O'Brien, 23, of Indianapolis, came out shooting for a takedown. No doubt expecting such a strategy, Arlovski sprawled and successfully defended the single-leg. Only more shots followed, however, and the young wrestler eventually grounded him late in the round. Arlovski dealt more damage from the bottom than he took, cutting O'Brien's scalp with an elbow.
Halfway into the second round, a lengthy series of takedown attempts again culminated with success for O'Brien. He couldn't hurt the 29-year-old native of Belarus on the ground, though.
After getting back to his feet, Arlovski used a body lock to put O'Brien's back to the mat. Even worse for the former Purdue University wrestler was the fact that Arlovski had landed in the mount. Punches followed, causing O'Brien to cover up until referee Mark Matheny intervened at 4:17.
Luigi Fioravanti (Pictures) (12-3) outwrestled Luke Cummo (Pictures) (6-5) for three rounds. Fighting out of Orlando, Fla., the 27-year-old Fioravanti scored four takedowns in the first five minutes. The second and third periods were no different.
Cummo, 27, of Long Island, N.Y., was active on his back throughout the fight. He rolled out from under Fioravanti several times, only to be taken down again before he could get his striking game going on the feet. The decision was unanimous for Fioravanti, 30-27 on all three cards.
Dustin Hazelett (Pictures) kicked Josh Koscheck (Pictures) in the head to start their welterweight fight, and Koscheck kicked him in the head to end it. The first strike caught Koscheck (10-2) behind the ear, stunning him. The American Kickboxing Academy welterweight recovered quickly, though, and commenced trading in an entertaining opening round.
Hazelett, 21, of Cincinnati, had a significant reach advantage and wasn't afraid of his athletic opponent. He threw several kicks, which Koscheck countered with better boxing. At one point, Hazelett, a Brazilian jiu-jitsu brown belt, grabbed a guillotine choke. Koscheck calmly defended it and later defended a triangle after he had scored a takedown.
In the second round, the 30-year-old Koscheck, fighting of San Jose, Calif., dug into his counterpart's body with punches. A right hand then prompted Hazelett (10-4) to cover up in a manner that left him open for a left head kick. Koscheck followed up with punches on the ground until Herb Dean (Pictures) stopped the fight at 1:24.
Diego Sanchez (Pictures) (18-2) dominated Sweden's David Bielkheden (Pictures) (12-6). Coming off back-to-back losses to Josh Koscheck and Jon Fitch, Sanchez shot through his opponent for a takedown to begin the fight. The 26-year-old "Ultimate Fighter" winner passed to half-guard, then threatened with a kimura that opened up a transition to the mount.
Bielkheden, 28, could not escape from the bottom. He bucked numerous times, but Sanchez stayed in the mount and battered him with punches until Bielkheden tapped at 4:43.
Cincinnati's Jorge Gurgel (Pictures) (12-3) used strikes on the ground to outpoint John Halverson (16-6) in a lightweight bout. The 31-year-old Gurgel did his best work during the second stanza. After freeing his neck from a guillotine attempt, he sat up in Halverson's guard and began hammering away with punches. Halverson, fighting out of Des Moines, Iowa, looked in trouble but survived the round.
Both fighters were exhausted in the third. The 35-year-old Halverson landed more in the standup exchanges, but Gurgel again scored on the ground to close the fight strongly. All three judges awarded the bout to Gurgel (29-28, 29-28, 30-27).