And he was the winner.
Henderson celebrated his return to the UFC with a unanimous decision over Rua on Saturday night in a slugfest that left both fighters bloodied and battered and had many at ringside buzzing long after the fight ended.
"That's without a doubt one of the top three best fights ever in MMA," UFC President Dana White said. "I have so much respect for both of those guys to dig down that deep in a five-round fight. That was like our Ali-Frazier III. It was incredible."
The 41-year-old Henderson (29-8) controlled the first three rounds of the fight, then held on over the final 10 minutes when Rua (20-6) made a furious comeback.
Both fighters' eyes were severely swollen afterward, while Rua's white-and-green shorts were nearly entirely covered in crimson from the blood that flowed from each man.
"That guy can take a punch," Henderson said, speaking from the middle of the ring before being taken to a local hospital for treatment. "I hit him hard and I thought I could finish him the first two or three rounds but he finished strong."
All three judges had Henderson winning 48-47 in the main event of UFC 139.
That puts him in line for a possible title shot against light heavyweight champion Jon Jones. White said Henderson could also drop down to the middleweight division for a crack at title-holder Anderson Silva.
"The guy's so talented, he can do both," White said. "I'm sure it will be a matter of timing, whichever one he can get first. There are guys lined up to fight for those titles but anything can happen. We'll see."
Henderson had not fought in the UFC since 2009 when he had a falling out with management. He joined Strikeforce and won that company's welterweight and middleweight championships before returning to the UFC.
Now Henderson is back in line for a title shot he felt he deserved before he left two years ago.
Wanderlei Silva is also back in contention in the middleweight division after getting got off the mat in the first round to knock out former Strikeforce champion Cung Le at 4:49 of the second in the co-main event.
Silva (34-11-1) stunned Le with a hard left and followed it up with a right jab to the chin and a stiff right foot to the side of Le's head. Silva then moved in and hit Le with four knee shots to the head that dropped the San Jose native.
Once Le (7-2) went down, Silva quickly pounced and landed several hard right hands before referee Dan Snell stepped in to stop it.
While a battered and bloodied Le was helped to his stool, Silva pranced around the ring and jumped on the cage as the crowd at HP Pavilion roared.
"He had tough kicks, strong kicks," Silva said about Le. "My coach told me we were going to attack more in the second round, and that was the plan."
Henderson came out the aggressor in his bout, pushing Rua against the cage and going for a standing chokehold submission early in the first round. Rua escaped but Henderson came back with several right hands to the head that opened a cut over Rua's left eye.
Rua, who lost the light heavyweight title to Jones in March, later had Henderson on the ground and landed several left hands before Henderson fought back with a left-right combination to Rua's head.
The pace slowed dramatically in the second round, though Henderson continued to score. He also bloodied Rua's nose with a hard left uppercut that landed squarely in the middle of Rua's face. Blood streamed down Rua's face the rest of the fight.
"I should have had him finished there," Henderson said. "His tank was running low there."
Still, the former UFC champ didn't go quietly.
After getting knocked to the floor following a hard right hand by Henderson, Rua was able to grab Henderson's left foot and went nearly had a submission hold locked in before Henderson escaped. Rua later had Henderson against the cage and scored with several punches.
Henderson missed on a rear chokehold early in the fourth and Rua nearly made him pay for it. He wobbled Henderson with a hard right hand then landed several left hands and right elbows after Henderson was down.
Rua continued to control the pace in the fifth while Henderson simply tried to hang on. Rua got on top of Henderson while both were on the mat and landed numerous shots to the head, but neither fighter could sustain much of an attack at the end.
"I had to finish strong," Rua told the crowd, before also being taken to the hospital.
The bout easily stood up as the fight of the night -- sharing honors with the Silva-Le fight. The Henderson-Rua bout likely will also be the fight of the year as well.
Silva's win puts him back in line for a possible title shot after many thought his career to be over only four months ago following a 27-second knockout loss to Chris Leben. It was Silva's sixth loss in eight fights and had White suggesting the former Pride champion should retire
Now Silva's a part of the title picture once again.
The 39-year-old Le set the tone early in his UFC debut, landing a spinning backfist early in the first round that put Silva down. The Brazilian got to his feet then landed a hard kick to the left side of Le's head. Silva couldn't follow up but opened a cut over Le's right eye.
The two fighters exchanged punches in the second round before Silva took over.
"I felt like I could go anywhere in this fight," said Faber, now the No. 1 contender for a shot at bantamweight champion Dominick Cruz. "Get ready Dominick. You can run but you can't hide."
Faber (26-5) landed a hard right uppercut that stunned Bowles early in the second round then followed it up with a left knee. As Bowles fell against the cage, Faber closed in and landed a series of right hands and forearms then finished the fight off by getting Bowles (10-2) to submit.
In a three-round welterweight bout, Martin Kampmann of Denmark won a split decision over Rick Story. Both fighters were bleeding from cuts over their eyes in the first round. Kampmann (18-5) also had a small cut on his forehead following a series of left jabs from Story (13-5) but came back to win the final two rounds for his first victory in more than 17 months.